Contract 0x2dcCe1586b1664f41C72206900e404Ec3cA130e0

 
 
Txn Hash Method
Block
From
To
Value [Txn Fee]
0x409c14e4abf0399a3a014f75e2eafb843e474e586925c48fb05d0b9c76608389Swap Underlying119892462021-10-22 9:31:3730 mins ago0x2e0f0fbf2114084dc445c59afa707be6fdaaba35 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.0022848
0x50fb07fa2a8273e15e25fbdf4a1c7c46a614f0a25568acf745e962689c8fb4a6Swap Underlying119886552021-10-22 9:02:0259 mins ago0xd0f1ea2c84182dd2858143b4003f115212b5401c IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002669952
0x6e805f8e425571c84061c92affb3a0cf498089982193baa15f41317702b2d1a6Swap Underlying119884462021-10-22 8:51:351 hr 10 mins ago0xa73fa9660897b42d42b91ce8a8cbc89c1d5fa699 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.00031383
0x77c613cfa8376882823a8dc8ee6077bafe8e1981571a8a338228b612730ed011Swap Underlying119884442021-10-22 8:51:291 hr 10 mins ago0xa73fa9660897b42d42b91ce8a8cbc89c1d5fa699 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002579808
0x15a52f11bd78cacbc1baafec65ebbfd16647e2b1ad5c9a926e0431508eb8f515Swap Underlying119881812021-10-22 8:38:161 hr 23 mins ago0xec36454a3449d960f62e7c5127cc8eb115d5fed7 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002441196
0x9d4534338e1b386632678c2315f577c9cf58f07fc64d978419299c8a638ecd96Swap Underlying119878002021-10-22 8:16:321 hr 45 mins ago0x548471686eb681c85bbc6b5540cb382437726d33 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.00227931
0xcc52d5a05cc948c4ba922edbcc4729cb3703fb78507a78be9186c8845af9599fSwap Underlying119867192021-10-22 7:21:252 hrs 40 mins ago0x731a75535ba8e4873ee79754b4db51b417005cd4 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.001965216
0x74a9c45a11abca09fac65f0421c0345194566f8260022c28ade8f8b62cfb0d66Swap Underlying119865722021-10-22 7:14:032 hrs 47 mins ago0x87b076e925dc371195eab25a0fe74dcbb5cb70f7 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002489664
0x3fe7f80c11f814836fa520d4dcb03806cc4800a9225a58e97c1616adb800f428Swap Underlying119862852021-10-22 6:59:413 hrs 2 mins ago0x7b58475a214907386228fdbc1ca0bfd162be55d4 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.00257988
0x7330a9e40cb00f112a5c1eebd7832f90da79f51dba97f2703705fa8e1cf337a6Swap Underlying119858292021-10-22 6:34:213 hrs 27 mins ago0x39a17cdcaf70024d23f2d6ac54cfb2dc00b263cc IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.00214984
0xe2baf2ea0f1c06da523af86e2f72dee869eb64f00c4c15e8b452190b0676fcd7Swap Underlying119853852021-10-22 6:12:083 hrs 49 mins ago0xaace7ed813f34b005ac31ca2ed93e5b01a8f819c IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.00237939
0xe05f91e1604ccf7b601fb705c8893874bf1b626bd3dc3514d883eaa66067fe76Swap Underlying119851622021-10-22 6:00:454 hrs 1 min ago0xcdc903632b212b00a0e7a679fbf41ae4bfac4b61 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.00207423
0xc1b875bbed0067c626c973e20ee7d23e9d0d04758302388d561558f8c9c33f2bSwap Underlying119850512021-10-22 5:54:544 hrs 6 mins ago0x3d1b88ab2760f1df9f9bf995e2b1f3568748ac47 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002579808
0x2ad691f8eaf0a35a235216087389d7bea3cad7996ec80d3659b51e52df185721Swap Underlying119833292021-10-22 4:16:495 hrs 44 mins ago0xd517e00351f8bb88f66632939523eb54ea29cce4 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002579736
0x854d63bbae4b86d332946ab9876bb9a85af5df3ebb44297b114b816696bc699aSwap Underlying119830052021-10-22 3:58:476 hrs 3 mins ago0x1830e4e417512774e88ebd8837a0ebc8bb56222b IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.00257988
0x9732c5218f08b4977ce7defb86cbca6e19e62a2d38f5269b6a108a64b43628f7Swap Underlying119815692021-10-22 2:44:467 hrs 17 mins ago0x8c33dbcfe8faabb4301a446b8500a3c13d9f5be3 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002579808
0xde7d4561fe3b9324a2572e02428041a07a5199c7ed4fc32c2f686040c05f959eSwap Underlying119809982021-10-22 2:16:127 hrs 45 mins ago0xe2b64581cacc4e0f65657f394564a2edfe05f660 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.00031383
0xd1ebf18ad3ee2e7a00cbe5c57f1e07c1f12babcfeeb048dc7bccfbfd411e2532Swap Underlying119809742021-10-22 2:15:007 hrs 46 mins ago0xe2b64581cacc4e0f65657f394564a2edfe05f660 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002579808
0xd870de4372336a8c33b1914240926715b71a0976e090ed74922be4bb4dccfc60Swap Underlying119801612021-10-22 1:33:368 hrs 28 mins ago0xaebe1dabbe47181b674057eb8550c281eaf44c5c IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002274744
0x5c0c3ae29d4555a776a0a447af1d3a12ac0e6e5b98f87f3990ac4bf8f1eff830Swap Underlying119799772021-10-22 1:24:228 hrs 37 mins ago0xa39595caf2f5b0119671dd937f3135498c8245a6 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002565858
0x9863e5a2662fa4b423406cf02191a12a4012ec76d0f07a4babf689b80d3e075bSwap Underlying119792932021-10-22 0:47:579 hrs 13 mins ago0x1830e4e417512774e88ebd8837a0ebc8bb56222b IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002579808
0xe1db09fbd11b179dc8a84bc20226defcebf45ebb7d3a30f5eea0189ba57d07f2Swap Underlying119784112021-10-22 0:02:529 hrs 58 mins ago0x02d6d611d5206866355e3a73df45cf8c734fa767 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002579664
0x2d262705261302d6ebc807591606fe2f446dab7db412e267dd1cb02d47efd8efSwap Underlying119778752021-10-21 23:36:0110 hrs 25 mins ago0x0be594b00ddb11730b5b81ada76617693bf4492e IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.002669808
0x302ce4c267dda40d545d678e8b2d20b7d605d86bcb2cccc6e7d9ebb1e246b1c4Swap Underlying119775522021-10-21 23:19:5210 hrs 41 mins ago0x1ef9a28c2f33b8297a5a687e49f3feaf14c8a461 IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.0022848
0x0e2c5d87b24c15bf8698b1c07aa527df803ce0b293c25de4477e52c3289f0d39Swap Underlying119768932021-10-21 22:46:5511 hrs 14 mins ago0x1830e4e417512774e88ebd8837a0ebc8bb56222b IN  0x2dcce1586b1664f41c72206900e404ec3ca130e00 BNB0.00257988
[ Download CSV Export 
Latest 2 internal transactions
Parent Txn Hash Block From To Value
0xc8f27c9629091a8f3dc6c66276d2b59c2e5036e0b560255bda1bf9303928e96673620172021-05-13 1:53:44162 days 8 hrs ago 0x2dcce1586b1664f41c72206900e404ec3ca130e0  Contract Creation0 BNB
0xc8f27c9629091a8f3dc6c66276d2b59c2e5036e0b560255bda1bf9303928e96673620172021-05-13 1:53:44162 days 8 hrs ago 0x2826dd9d427d441471fe98204b4cf1a6d02ec5fb  Contract Creation0 BNB
[ Download CSV Export 
Loading
This contract contains unverified libraries: AmplificationUtils

Minimal Proxy Contract for 0x2dcCe1586b1664f41C72206900e404Ec3cA130e0

Contract Name:
MetaSwap

Compiler Version
v0.6.12+commit.27d51765

Optimization Enabled:
Yes with 10000 runs

Other Settings:
default evmVersion, MIT license
Decompile ByteCode

Contract Source Code (Solidity Standard Json-Input format)

File 1 of 23 : OwnableUpgradeable.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "../utils/ContextUpgradeable.sol";
import "../proxy/Initializable.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract OwnableUpgradeable is Initializable, ContextUpgradeable {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    function __Ownable_init() internal initializer {
        __Context_init_unchained();
        __Ownable_init_unchained();
    }

    function __Ownable_init_unchained() internal initializer {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
    uint256[49] private __gap;
}

File 2 of 23 : Initializable.sol
// SPDX-License-Identifier: MIT

// solhint-disable-next-line compiler-version
pragma solidity >=0.4.24 <0.8.0;

import "../utils/AddressUpgradeable.sol";

/**
 * @dev This is a base contract to aid in writing upgradeable contracts, or any kind of contract that will be deployed
 * behind a proxy. Since a proxied contract can't have a constructor, it's common to move constructor logic to an
 * external initializer function, usually called `initialize`. It then becomes necessary to protect this initializer
 * function so it can only be called once. The {initializer} modifier provided by this contract will have this effect.
 *
 * TIP: To avoid leaving the proxy in an uninitialized state, the initializer function should be called as early as
 * possible by providing the encoded function call as the `_data` argument to {UpgradeableProxy-constructor}.
 *
 * CAUTION: When used with inheritance, manual care must be taken to not invoke a parent initializer twice, or to ensure
 * that all initializers are idempotent. This is not verified automatically as constructors are by Solidity.
 */
abstract contract Initializable {

    /**
     * @dev Indicates that the contract has been initialized.
     */
    bool private _initialized;

    /**
     * @dev Indicates that the contract is in the process of being initialized.
     */
    bool private _initializing;

    /**
     * @dev Modifier to protect an initializer function from being invoked twice.
     */
    modifier initializer() {
        require(_initializing || _isConstructor() || !_initialized, "Initializable: contract is already initialized");

        bool isTopLevelCall = !_initializing;
        if (isTopLevelCall) {
            _initializing = true;
            _initialized = true;
        }

        _;

        if (isTopLevelCall) {
            _initializing = false;
        }
    }

    /// @dev Returns true if and only if the function is running in the constructor
    function _isConstructor() private view returns (bool) {
        return !AddressUpgradeable.isContract(address(this));
    }
}

File 3 of 23 : AddressUpgradeable.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.2 <0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library AddressUpgradeable {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

File 4 of 23 : ContextUpgradeable.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;
import "../proxy/Initializable.sol";

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract ContextUpgradeable is Initializable {
    function __Context_init() internal initializer {
        __Context_init_unchained();
    }

    function __Context_init_unchained() internal initializer {
    }
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
    uint256[50] private __gap;
}

File 5 of 23 : PausableUpgradeable.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "./ContextUpgradeable.sol";
import "../proxy/Initializable.sol";

/**
 * @dev Contract module which allows children to implement an emergency stop
 * mechanism that can be triggered by an authorized account.
 *
 * This module is used through inheritance. It will make available the
 * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
 * the functions of your contract. Note that they will not be pausable by
 * simply including this module, only once the modifiers are put in place.
 */
abstract contract PausableUpgradeable is Initializable, ContextUpgradeable {
    /**
     * @dev Emitted when the pause is triggered by `account`.
     */
    event Paused(address account);

    /**
     * @dev Emitted when the pause is lifted by `account`.
     */
    event Unpaused(address account);

    bool private _paused;

    /**
     * @dev Initializes the contract in unpaused state.
     */
    function __Pausable_init() internal initializer {
        __Context_init_unchained();
        __Pausable_init_unchained();
    }

    function __Pausable_init_unchained() internal initializer {
        _paused = false;
    }

    /**
     * @dev Returns true if the contract is paused, and false otherwise.
     */
    function paused() public view virtual returns (bool) {
        return _paused;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is not paused.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    modifier whenNotPaused() {
        require(!paused(), "Pausable: paused");
        _;
    }

    /**
     * @dev Modifier to make a function callable only when the contract is paused.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    modifier whenPaused() {
        require(paused(), "Pausable: not paused");
        _;
    }

    /**
     * @dev Triggers stopped state.
     *
     * Requirements:
     *
     * - The contract must not be paused.
     */
    function _pause() internal virtual whenNotPaused {
        _paused = true;
        emit Paused(_msgSender());
    }

    /**
     * @dev Returns to normal state.
     *
     * Requirements:
     *
     * - The contract must be paused.
     */
    function _unpause() internal virtual whenPaused {
        _paused = false;
        emit Unpaused(_msgSender());
    }
    uint256[49] private __gap;
}

File 6 of 23 : ReentrancyGuardUpgradeable.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;
import "../proxy/Initializable.sol";

/**
 * @dev Contract module that helps prevent reentrant calls to a function.
 *
 * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
 * available, which can be applied to functions to make sure there are no nested
 * (reentrant) calls to them.
 *
 * Note that because there is a single `nonReentrant` guard, functions marked as
 * `nonReentrant` may not call one another. This can be worked around by making
 * those functions `private`, and then adding `external` `nonReentrant` entry
 * points to them.
 *
 * TIP: If you would like to learn more about reentrancy and alternative ways
 * to protect against it, check out our blog post
 * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
 */
abstract contract ReentrancyGuardUpgradeable is Initializable {
    // Booleans are more expensive than uint256 or any type that takes up a full
    // word because each write operation emits an extra SLOAD to first read the
    // slot's contents, replace the bits taken up by the boolean, and then write
    // back. This is the compiler's defense against contract upgrades and
    // pointer aliasing, and it cannot be disabled.

    // The values being non-zero value makes deployment a bit more expensive,
    // but in exchange the refund on every call to nonReentrant will be lower in
    // amount. Since refunds are capped to a percentage of the total
    // transaction's gas, it is best to keep them low in cases like this one, to
    // increase the likelihood of the full refund coming into effect.
    uint256 private constant _NOT_ENTERED = 1;
    uint256 private constant _ENTERED = 2;

    uint256 private _status;

    function __ReentrancyGuard_init() internal initializer {
        __ReentrancyGuard_init_unchained();
    }

    function __ReentrancyGuard_init_unchained() internal initializer {
        _status = _NOT_ENTERED;
    }

    /**
     * @dev Prevents a contract from calling itself, directly or indirectly.
     * Calling a `nonReentrant` function from another `nonReentrant`
     * function is not supported. It is possible to prevent this from happening
     * by making the `nonReentrant` function external, and make it call a
     * `private` function that does the actual work.
     */
    modifier nonReentrant() {
        // On the first call to nonReentrant, _notEntered will be true
        require(_status != _ENTERED, "ReentrancyGuard: reentrant call");

        // Any calls to nonReentrant after this point will fail
        _status = _ENTERED;

        _;

        // By storing the original value once again, a refund is triggered (see
        // https://eips.ethereum.org/EIPS/eip-2200)
        _status = _NOT_ENTERED;
    }
    uint256[49] private __gap;
}

File 7 of 23 : Ownable.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "../utils/Context.sol";
/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
abstract contract Ownable is Context {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */
    constructor () internal {
        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);
    }

    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view virtual returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(owner() == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }
}

File 8 of 23 : SafeMath.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        uint256 c = a + b;
        if (c < a) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the substraction of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b > a) return (false, 0);
        return (true, a - b);
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
     *
     * _Available since v3.4._
     */
    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) return (true, 0);
        uint256 c = a * b;
        if (c / a != b) return (false, 0);
        return (true, c);
    }

    /**
     * @dev Returns the division of two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a / b);
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
     *
     * _Available since v3.4._
     */
    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
        if (b == 0) return (false, 0);
        return (true, a % b);
    }

    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");
        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b <= a, "SafeMath: subtraction overflow");
        return a - b;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a == 0) return 0;
        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");
        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: division by zero");
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        require(b > 0, "SafeMath: modulo by zero");
        return a % b;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {trySub}.
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        return a - b;
    }

    /**
     * @dev Returns the integer division of two unsigned integers, reverting with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryDiv}.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a / b;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * reverting with custom message when dividing by zero.
     *
     * CAUTION: This function is deprecated because it requires allocating memory for the error
     * message unnecessarily. For custom revert reasons use {tryMod}.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        return a % b;
    }
}

File 9 of 23 : ERC20.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "../../utils/Context.sol";
import "./IERC20.sol";
import "../../math/SafeMath.sol";

/**
 * @dev Implementation of the {IERC20} interface.
 *
 * This implementation is agnostic to the way tokens are created. This means
 * that a supply mechanism has to be added in a derived contract using {_mint}.
 * For a generic mechanism see {ERC20PresetMinterPauser}.
 *
 * TIP: For a detailed writeup see our guide
 * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
 * to implement supply mechanisms].
 *
 * We have followed general OpenZeppelin guidelines: functions revert instead
 * of returning `false` on failure. This behavior is nonetheless conventional
 * and does not conflict with the expectations of ERC20 applications.
 *
 * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
 * This allows applications to reconstruct the allowance for all accounts just
 * by listening to said events. Other implementations of the EIP may not emit
 * these events, as it isn't required by the specification.
 *
 * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
 * functions have been added to mitigate the well-known issues around setting
 * allowances. See {IERC20-approve}.
 */
contract ERC20 is Context, IERC20 {
    using SafeMath for uint256;

    mapping (address => uint256) private _balances;

    mapping (address => mapping (address => uint256)) private _allowances;

    uint256 private _totalSupply;

    string private _name;
    string private _symbol;
    uint8 private _decimals;

    /**
     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with
     * a default value of 18.
     *
     * To select a different value for {decimals}, use {_setupDecimals}.
     *
     * All three of these values are immutable: they can only be set once during
     * construction.
     */
    constructor (string memory name_, string memory symbol_) public {
        _name = name_;
        _symbol = symbol_;
        _decimals = 18;
    }

    /**
     * @dev Returns the name of the token.
     */
    function name() public view virtual returns (string memory) {
        return _name;
    }

    /**
     * @dev Returns the symbol of the token, usually a shorter version of the
     * name.
     */
    function symbol() public view virtual returns (string memory) {
        return _symbol;
    }

    /**
     * @dev Returns the number of decimals used to get its user representation.
     * For example, if `decimals` equals `2`, a balance of `505` tokens should
     * be displayed to a user as `5,05` (`505 / 10 ** 2`).
     *
     * Tokens usually opt for a value of 18, imitating the relationship between
     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is
     * called.
     *
     * NOTE: This information is only used for _display_ purposes: it in
     * no way affects any of the arithmetic of the contract, including
     * {IERC20-balanceOf} and {IERC20-transfer}.
     */
    function decimals() public view virtual returns (uint8) {
        return _decimals;
    }

    /**
     * @dev See {IERC20-totalSupply}.
     */
    function totalSupply() public view virtual override returns (uint256) {
        return _totalSupply;
    }

    /**
     * @dev See {IERC20-balanceOf}.
     */
    function balanceOf(address account) public view virtual override returns (uint256) {
        return _balances[account];
    }

    /**
     * @dev See {IERC20-transfer}.
     *
     * Requirements:
     *
     * - `recipient` cannot be the zero address.
     * - the caller must have a balance of at least `amount`.
     */
    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(_msgSender(), recipient, amount);
        return true;
    }

    /**
     * @dev See {IERC20-allowance}.
     */
    function allowance(address owner, address spender) public view virtual override returns (uint256) {
        return _allowances[owner][spender];
    }

    /**
     * @dev See {IERC20-approve}.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function approve(address spender, uint256 amount) public virtual override returns (bool) {
        _approve(_msgSender(), spender, amount);
        return true;
    }

    /**
     * @dev See {IERC20-transferFrom}.
     *
     * Emits an {Approval} event indicating the updated allowance. This is not
     * required by the EIP. See the note at the beginning of {ERC20}.
     *
     * Requirements:
     *
     * - `sender` and `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     * - the caller must have allowance for ``sender``'s tokens of at least
     * `amount`.
     */
    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {
        _transfer(sender, recipient, amount);
        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, "ERC20: transfer amount exceeds allowance"));
        return true;
    }

    /**
     * @dev Atomically increases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     */
    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));
        return true;
    }

    /**
     * @dev Atomically decreases the allowance granted to `spender` by the caller.
     *
     * This is an alternative to {approve} that can be used as a mitigation for
     * problems described in {IERC20-approve}.
     *
     * Emits an {Approval} event indicating the updated allowance.
     *
     * Requirements:
     *
     * - `spender` cannot be the zero address.
     * - `spender` must have allowance for the caller of at least
     * `subtractedValue`.
     */
    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, "ERC20: decreased allowance below zero"));
        return true;
    }

    /**
     * @dev Moves tokens `amount` from `sender` to `recipient`.
     *
     * This is internal function is equivalent to {transfer}, and can be used to
     * e.g. implement automatic token fees, slashing mechanisms, etc.
     *
     * Emits a {Transfer} event.
     *
     * Requirements:
     *
     * - `sender` cannot be the zero address.
     * - `recipient` cannot be the zero address.
     * - `sender` must have a balance of at least `amount`.
     */
    function _transfer(address sender, address recipient, uint256 amount) internal virtual {
        require(sender != address(0), "ERC20: transfer from the zero address");
        require(recipient != address(0), "ERC20: transfer to the zero address");

        _beforeTokenTransfer(sender, recipient, amount);

        _balances[sender] = _balances[sender].sub(amount, "ERC20: transfer amount exceeds balance");
        _balances[recipient] = _balances[recipient].add(amount);
        emit Transfer(sender, recipient, amount);
    }

    /** @dev Creates `amount` tokens and assigns them to `account`, increasing
     * the total supply.
     *
     * Emits a {Transfer} event with `from` set to the zero address.
     *
     * Requirements:
     *
     * - `to` cannot be the zero address.
     */
    function _mint(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: mint to the zero address");

        _beforeTokenTransfer(address(0), account, amount);

        _totalSupply = _totalSupply.add(amount);
        _balances[account] = _balances[account].add(amount);
        emit Transfer(address(0), account, amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, reducing the
     * total supply.
     *
     * Emits a {Transfer} event with `to` set to the zero address.
     *
     * Requirements:
     *
     * - `account` cannot be the zero address.
     * - `account` must have at least `amount` tokens.
     */
    function _burn(address account, uint256 amount) internal virtual {
        require(account != address(0), "ERC20: burn from the zero address");

        _beforeTokenTransfer(account, address(0), amount);

        _balances[account] = _balances[account].sub(amount, "ERC20: burn amount exceeds balance");
        _totalSupply = _totalSupply.sub(amount);
        emit Transfer(account, address(0), amount);
    }

    /**
     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
     *
     * This internal function is equivalent to `approve`, and can be used to
     * e.g. set automatic allowances for certain subsystems, etc.
     *
     * Emits an {Approval} event.
     *
     * Requirements:
     *
     * - `owner` cannot be the zero address.
     * - `spender` cannot be the zero address.
     */
    function _approve(address owner, address spender, uint256 amount) internal virtual {
        require(owner != address(0), "ERC20: approve from the zero address");
        require(spender != address(0), "ERC20: approve to the zero address");

        _allowances[owner][spender] = amount;
        emit Approval(owner, spender, amount);
    }

    /**
     * @dev Sets {decimals} to a value other than the default one of 18.
     *
     * WARNING: This function should only be called from the constructor. Most
     * applications that interact with token contracts will not expect
     * {decimals} to ever change, and may work incorrectly if it does.
     */
    function _setupDecimals(uint8 decimals_) internal virtual {
        _decimals = decimals_;
    }

    /**
     * @dev Hook that is called before any transfer of tokens. This includes
     * minting and burning.
     *
     * Calling conditions:
     *
     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
     * will be to transferred to `to`.
     * - when `from` is zero, `amount` tokens will be minted for `to`.
     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
     * - `from` and `to` are never both zero.
     *
     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
     */
    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }
}

File 10 of 23 : ERC20Burnable.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "../../utils/Context.sol";
import "./ERC20.sol";

/**
 * @dev Extension of {ERC20} that allows token holders to destroy both their own
 * tokens and those that they have an allowance for, in a way that can be
 * recognized off-chain (via event analysis).
 */
abstract contract ERC20Burnable is Context, ERC20 {
    using SafeMath for uint256;

    /**
     * @dev Destroys `amount` tokens from the caller.
     *
     * See {ERC20-_burn}.
     */
    function burn(uint256 amount) public virtual {
        _burn(_msgSender(), amount);
    }

    /**
     * @dev Destroys `amount` tokens from `account`, deducting from the caller's
     * allowance.
     *
     * See {ERC20-_burn} and {ERC20-allowance}.
     *
     * Requirements:
     *
     * - the caller must have allowance for ``accounts``'s tokens of at least
     * `amount`.
     */
    function burnFrom(address account, uint256 amount) public virtual {
        uint256 decreasedAllowance = allowance(account, _msgSender()).sub(amount, "ERC20: burn amount exceeds allowance");

        _approve(account, _msgSender(), decreasedAllowance);
        _burn(account, amount);
    }
}

File 11 of 23 : IERC20.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

File 12 of 23 : SafeERC20.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

import "./IERC20.sol";
import "../../math/SafeMath.sol";
import "../../utils/Address.sol";

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using SafeMath for uint256;
    using Address for address;

    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

File 13 of 23 : Address.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.2 <0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
        return functionDelegateCall(target, data, "Address: low-level delegate call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a delegate call.
     *
     * _Available since v3.4._
     */
    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        require(isContract(target), "Address: delegate call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.delegatecall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

File 14 of 23 : Context.sol
// SPDX-License-Identifier: MIT

pragma solidity >=0.6.0 <0.8.0;

/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
abstract contract Context {
    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }
}

File 15 of 23 : AmplificationUtils.sol
// SPDX-License-Identifier: MIT

import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "./SwapUtils.sol";

pragma solidity 0.6.12;

library AmplificationUtils {
    using SafeMath for uint256;

    event RampA(
        uint256 oldA,
        uint256 newA,
        uint256 initialTime,
        uint256 futureTime
    );
    event StopRampA(uint256 currentA, uint256 time);

    // Constant values used in ramping A calculations
    uint256 public constant A_PRECISION = 100;
    uint256 public constant MAX_A = 10**6;
    uint256 private constant MAX_A_CHANGE = 2;
    uint256 private constant MIN_RAMP_TIME = 14 days;

    /**
     * @notice Start ramping up or down A parameter towards given futureA_ and futureTime_
     * Checks if the change is too rapid, and commits the new A value only when it falls under
     * the limit range.
     * @param self Swap struct to update
     * @param futureA_ the new A to ramp towards
     * @param futureTime_ timestamp when the new A should be reached
     */
    function rampA(
        SwapUtils.Swap storage self,
        uint256 initialAPrecise,
        uint256 futureA_,
        uint256 futureTime_
    ) external {
        require(
            block.timestamp >= self.initialATime.add(1 days),
            "Wait 1 day before starting ramp"
        );
        require(
            futureTime_ >= block.timestamp.add(MIN_RAMP_TIME),
            "Insufficient ramp time"
        );
        require(
            futureA_ > 0 && futureA_ < MAX_A,
            "futureA_ must be > 0 and < MAX_A"
        );

        uint256 futureAPrecise = futureA_.mul(A_PRECISION);

        if (futureAPrecise < initialAPrecise) {
            require(
                futureAPrecise.mul(MAX_A_CHANGE) >= initialAPrecise,
                "futureA_ is too small"
            );
        } else {
            require(
                futureAPrecise <= initialAPrecise.mul(MAX_A_CHANGE),
                "futureA_ is too large"
            );
        }

        self.initialA = initialAPrecise;
        self.futureA = futureAPrecise;
        self.initialATime = block.timestamp;
        self.futureATime = futureTime_;

        emit RampA(
            initialAPrecise,
            futureAPrecise,
            block.timestamp,
            futureTime_
        );
    }

    /**
     * @notice Stops ramping A immediately. Once this function is called, rampA()
     * cannot be called for another 24 hours
     * @param self Swap struct to update
     */
    function stopRampA(SwapUtils.Swap storage self, uint256 currentA) external {
        require(self.futureATime > block.timestamp, "Ramp is already stopped");

        self.initialA = currentA;
        self.futureA = currentA;
        self.initialATime = block.timestamp;
        self.futureATime = block.timestamp;

        emit StopRampA(currentA, block.timestamp);
    }
}

File 16 of 23 : LPToken.sol
// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;

import "@openzeppelin/contracts/token/ERC20/ERC20Burnable.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/math/SafeMath.sol";
import "./interfaces/ISwap.sol";

/**
 * @title Liquidity Provider Token
 * @notice This token is an ERC20 detailed token with added capability to be minted by the owner.
 * It is used to represent user's shares when providing liquidity to swap contracts.
 */
contract LPToken is ERC20Burnable, Ownable {
    using SafeMath for uint256;

    // Address of the swap contract that owns this LP token. When a user adds liquidity to the swap contract,
    // they receive a proportionate amount of this LPToken.
    ISwap public swap;

    /**
     * @notice Deploys LPToken contract with given name, symbol, and decimals
     * @dev the caller of this constructor will become the owner of this contract
     * @param name_ name of this token
     * @param symbol_ symbol of this token
     * @param decimals_ number of decimals this token will be based on
     */
    constructor(
        string memory name_,
        string memory symbol_,
        uint8 decimals_
    ) public ERC20(name_, symbol_) {
        _setupDecimals(decimals_);
        swap = ISwap(_msgSender());
    }

    /**
     * @notice Mints the given amount of LPToken to the recipient.
     * @dev only owner can call this mint function
     * @param recipient address of account to receive the tokens
     * @param amount amount of tokens to mint
     */
    function mint(address recipient, uint256 amount) external onlyOwner {
        require(amount != 0, "amount == 0");
        _mint(recipient, amount);
    }

    /**
     * @dev Overrides ERC20._beforeTokenTransfer() which get called on every transfers including
     * minting and burning. This ensures that swap.updateUserWithdrawFees are called everytime.
     */
    function _beforeTokenTransfer(
        address from,
        address to,
        uint256 amount
    ) internal override(ERC20) {
        super._beforeTokenTransfer(from, to, amount);
        swap.updateUserWithdrawFee(to, amount);
    }
}

File 17 of 23 : MathUtils.sol
// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;

import "@openzeppelin/contracts/math/SafeMath.sol";

/**
 * @title MathUtils library
 * @notice A library to be used in conjunction with SafeMath. Contains functions for calculating
 * differences between two uint256.
 */
library MathUtils {
    /**
     * @notice Compares a and b and returns true if the difference between a and b
     *         is less than 1 or equal to each other.
     * @param a uint256 to compare with
     * @param b uint256 to compare with
     * @return True if the difference between a and b is less than 1 or equal,
     *         otherwise return false
     */
    function within1(uint256 a, uint256 b) internal pure returns (bool) {
        return (difference(a, b) <= 1);
    }

    /**
     * @notice Calculates absolute difference between a and b
     * @param a uint256 to compare with
     * @param b uint256 to compare with
     * @return Difference between a and b
     */
    function difference(uint256 a, uint256 b) internal pure returns (uint256) {
        if (a > b) {
            return a - b;
        }
        return b - a;
    }
}

File 18 of 23 : OwnerPausableUpgradeable.sol
// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;

import "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
import "@openzeppelin/contracts-upgradeable/utils/PausableUpgradeable.sol";

/**
 * @title OwnerPausable
 * @notice An ownable contract allows the owner to pause and unpause the
 * contract without a delay.
 * @dev Only methods using the provided modifiers will be paused.
 */
abstract contract OwnerPausableUpgradeable is
    OwnableUpgradeable,
    PausableUpgradeable
{
    function __OwnerPausable_init() internal initializer {
        __Context_init_unchained();
        __Ownable_init_unchained();
        __Pausable_init_unchained();
    }

    /**
     * @notice Pause the contract. Revert if already paused.
     */
    function pause() external onlyOwner {
        PausableUpgradeable._pause();
    }

    /**
     * @notice Unpause the contract. Revert if already unpaused.
     */
    function unpause() external onlyOwner {
        PausableUpgradeable._unpause();
    }
}

File 19 of 23 : Swap.sol
// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;

import "@openzeppelin/contracts/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts-upgradeable/utils/ReentrancyGuardUpgradeable.sol";
import "./OwnerPausableUpgradeable.sol";
import "./SwapUtils.sol";
import "./MathUtils.sol";
import "./AmplificationUtils.sol";

/**
 * @title Swap - A StableSwap implementation in solidity.
 * @notice This contract is responsible for custody of closely pegged assets (eg. group of stablecoins)
 * and automatic market making system. Users become an LP (Liquidity Provider) by depositing their tokens
 * in desired ratios for an exchange of the pool token that represents their share of the pool.
 * Users can burn pool tokens and withdraw their share of token(s).
 *
 * Each time a swap between the pooled tokens happens, a set fee incurs which effectively gets
 * distributed to the LPs.
 *
 * In case of emergencies, admin can pause additional deposits, swaps, or single-asset withdraws - which
 * stops the ratio of the tokens in the pool from changing.
 * Users can always withdraw their tokens via multi-asset withdraws.
 *
 * @dev Most of the logic is stored as a library `SwapUtils` for the sake of reducing contract's
 * deployment size.
 */
contract Swap is OwnerPausableUpgradeable, ReentrancyGuardUpgradeable {
    using SafeERC20 for IERC20;
    using SafeMath for uint256;
    using SwapUtils for SwapUtils.Swap;
    using AmplificationUtils for SwapUtils.Swap;

    // Struct storing data responsible for automatic market maker functionalities. In order to
    // access this data, this contract uses SwapUtils library. For more details, see SwapUtils.sol
    SwapUtils.Swap public swapStorage;

    // True if the contract is initialized.
    bool private initialized = false;

    // Maps token address to an index in the pool. Used to prevent duplicate tokens in the pool.
    // getTokenIndex function also relies on this mapping to retrieve token index.
    mapping(address => uint8) private tokenIndexes;

    /*** EVENTS ***/

    // events replicated from SwapUtils to make the ABI easier for dumb
    // clients
    event TokenSwap(
        address indexed buyer,
        uint256 tokensSold,
        uint256 tokensBought,
        uint128 soldId,
        uint128 boughtId
    );
    event AddLiquidity(
        address indexed provider,
        uint256[] tokenAmounts,
        uint256[] fees,
        uint256 invariant,
        uint256 lpTokenSupply
    );
    event RemoveLiquidity(
        address indexed provider,
        uint256[] tokenAmounts,
        uint256 lpTokenSupply
    );
    event RemoveLiquidityOne(
        address indexed provider,
        uint256 lpTokenAmount,
        uint256 lpTokenSupply,
        uint256 boughtId,
        uint256 tokensBought
    );
    event RemoveLiquidityImbalance(
        address indexed provider,
        uint256[] tokenAmounts,
        uint256[] fees,
        uint256 invariant,
        uint256 lpTokenSupply
    );
    event NewAdminFee(uint256 newAdminFee);
    event NewSwapFee(uint256 newSwapFee);
    event NewDepositFee(uint256 newDepositFee);
    event NewWithdrawFee(uint256 newWithdrawFee);
    event RampA(
        uint256 oldA,
        uint256 newA,
        uint256 initialTime,
        uint256 futureTime
    );
    event StopRampA(uint256 currentA, uint256 time);

    /**
     * @notice Initializes this Swap contract with the given parameters.
     * This will also deploy the LPToken that represents users
     * LP position. The owner of LPToken will be this contract - which means
     * only this contract is allowed to mint new tokens.
     *
     * @param _pooledTokens an array of ERC20s this pool will accept
     * @param decimals the decimals to use for each pooled token,
     * eg 8 for WBTC. Cannot be larger than POOL_PRECISION_DECIMALS
     * @param lpTokenName the long-form name of the token to be deployed
     * @param lpTokenSymbol the short symbol for the token to be deployed
     * @param _a the amplification coefficient * n * (n - 1). See the
     * StableSwap paper for details
     * @param _fee default swap fee to be initialized with
     * @param _adminFee default adminFee to be initialized with
     * @param _depositFee default depositFee to be initialized with
     * @param _withdrawFee default withdrawFee to be initialized with
     * @param _devaddr default _devaddr to be initialized with
     */
    function initialize(
        IERC20[] memory _pooledTokens,
        uint8[] memory decimals,
        string memory lpTokenName,
        string memory lpTokenSymbol,
        uint256 _a,
        uint256 _fee,
        uint256 _adminFee,
        uint256 _depositFee,
        uint256 _withdrawFee,
        address _devaddr
    ) public virtual initializer {
        __OwnerPausable_init();
        __ReentrancyGuard_init();
        // Check _pooledTokens and precisions parameter
        require(_pooledTokens.length > 1, "_pooledTokens.length <= 1");
        require(_pooledTokens.length <= 32, "_pooledTokens.length > 32");
        require(
            _pooledTokens.length == decimals.length,
            "_pooledTokens decimals mismatch"
        );

        uint256[] memory precisionMultipliers = new uint256[](decimals.length);

        for (uint8 i = 0; i < _pooledTokens.length; i++) {
            if (i > 0) {
                // Check if index is already used. Check if 0th element is a duplicate.
                require(
                    tokenIndexes[address(_pooledTokens[i])] == 0 &&
                        _pooledTokens[0] != _pooledTokens[i],
                    "Duplicate tokens"
                );
            }
            require(
                address(_pooledTokens[i]) != address(0),
                "The 0 address isn't an ERC-20"
            );
            require(
                decimals[i] <= SwapUtils.POOL_PRECISION_DECIMALS,
                "Token decimals exceeds max"
            );
            precisionMultipliers[i] =
                10 **
                    uint256(SwapUtils.POOL_PRECISION_DECIMALS).sub(
                        uint256(decimals[i])
                    );
            tokenIndexes[address(_pooledTokens[i])] = i;
        }

        // Check _a, _fee, _adminFee, _depositFee, _withdrawFee parameters
        require(_a < AmplificationUtils.MAX_A, "_a exceeds maximum");
        require(_fee < SwapUtils.MAX_SWAP_FEE, "_fee exceeds maximum");
        require(
            _adminFee < SwapUtils.MAX_ADMIN_FEE,
            "_adminFee exceeds maximum"
        );
        require(
            _withdrawFee < SwapUtils.MAX_WITHDRAW_FEE,
            "_withdrawFee exceeds maximum"
        );
        require(
            _depositFee < SwapUtils.MAX_DEPOSIT_FEE,
            "_depositFee exceeds maximum"
        );

        // Initialize swapStorage struct
        swapStorage.lpToken = new LPToken(
            lpTokenName,
            lpTokenSymbol,
            SwapUtils.POOL_PRECISION_DECIMALS
        );
        swapStorage.pooledTokens = _pooledTokens;
        swapStorage.tokenPrecisionMultipliers = precisionMultipliers;
        swapStorage.balances = new uint256[](_pooledTokens.length);
        swapStorage.initialA = _a.mul(SwapUtils.A_PRECISION);
        swapStorage.futureA = _a.mul(SwapUtils.A_PRECISION);
        swapStorage.initialATime = 0;
        swapStorage.futureATime = 0;
        swapStorage.swapFee = _fee;
        swapStorage.adminFee = _adminFee;
        swapStorage.defaultDepositFee = _depositFee;
        swapStorage.defaultWithdrawFee = _withdrawFee;
        swapStorage.devaddr = _devaddr;
    }

    /*** MODIFIERS ***/

    /**
     * @notice Modifier to check deadline against current timestamp
     * @param deadline latest timestamp to accept this transaction
     */
    modifier deadlineCheck(uint256 deadline) {
        require(block.timestamp <= deadline, "Deadline not met");
        _;
    }

    /*** VIEW FUNCTIONS ***/

    /**
     * @notice Return A, the amplification coefficient * n * (n - 1)
     * @dev See the StableSwap paper for details
     * @return A parameter
     */
    function getA() external view virtual returns (uint256) {
        return swapStorage.getA();
    }

    /**
     * @notice Return A in its raw precision form
     * @dev See the StableSwap paper for details
     * @return A parameter in its raw precision form
     */
    function getAPrecise() external view virtual returns (uint256) {
        return swapStorage.getAPrecise();
    }

    /**
     * @notice Return address of the pooled token at given index. Reverts if tokenIndex is out of range.
     * @param index the index of the token
     * @return address of the token at given index
     */
    function getToken(uint8 index) public view virtual returns (IERC20) {
        require(index < swapStorage.pooledTokens.length, "Out of range");
        return swapStorage.pooledTokens[index];
    }

    /**
     * @notice Return the index of the given token address. Reverts if no matching
     * token is found.
     * @param tokenAddress address of the token
     * @return the index of the given token address
     */
    function getTokenIndex(address tokenAddress)
        public
        view
        virtual
        returns (uint8)
    {
        uint8 index = tokenIndexes[tokenAddress];
        require(
            address(getToken(index)) == tokenAddress,
            "Token does not exist"
        );
        return index;
    }

    /**
     * @notice Return timestamp of last deposit of given address
     * @return timestamp of the last deposit made by the given address
     */
    function getDepositTimestamp(address user)
        external
        view
        virtual
        returns (uint256)
    {
        return swapStorage.getDepositTimestamp(user);
    }

    /**
     * @notice Return current balance of the pooled token at given index
     * @param index the index of the token
     * @return current balance of the pooled token at given index with token's native precision
     */
    function getTokenBalance(uint8 index)
        external
        view
        virtual
        returns (uint256)
    {
        require(index < swapStorage.pooledTokens.length, "Index out of range");
        return swapStorage.balances[index];
    }

    /**
     * @notice Get the virtual price, to help calculate profit
     * @return the virtual price, scaled to the POOL_PRECISION_DECIMALS
     */
    function getVirtualPrice() external view virtual returns (uint256) {
        return swapStorage.getVirtualPrice();
    }

    /**
     * @notice Calculate amount of tokens you receive on swap
     * @param tokenIndexFrom the token the user wants to sell
     * @param tokenIndexTo the token the user wants to buy
     * @param dx the amount of tokens the user wants to sell. If the token charges
     * a fee on transfers, use the amount that gets transferred after the fee.
     * @return amount of tokens the user will receive
     */
    function calculateSwap(
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx
    ) external view virtual returns (uint256) {
        return swapStorage.calculateSwap(tokenIndexFrom, tokenIndexTo, dx);
    }

    /**
     * @notice A simple method to calculate prices from deposits or
     * withdrawals, excluding fees but including slippage. This is
     * helpful as an input into the various "min" parameters on calls
     * to fight front-running
     *
     * @dev This shouldn't be used outside frontends for user estimates.
     *
     * @param account address that is depositing or withdrawing tokens
     * @param amounts an array of token amounts to deposit or withdrawal,
     * corresponding to pooledTokens. The amount should be in each
     * pooled token's native precision. If a token charges a fee on transfers,
     * use the amount that gets transferred after the fee.
     * @param deposit whether this is a deposit or a withdrawal
     * @return token amount the user will receive
     */
    function calculateTokenAmount(
        address account,
        uint256[] calldata amounts,
        bool deposit
    ) external view virtual returns (uint256) {
        return swapStorage.calculateTokenAmount(account, amounts, deposit);
    }

    /**
     * @notice A simple method to calculate amount of each underlying
     * tokens that is returned upon burning given amount of LP tokens
     * @param account the address that is withdrawing tokens
     * @param amount the amount of LP tokens that would be burned on withdrawal
     * @return array of token balances that the user will receive
     */
    function calculateRemoveLiquidity(address account, uint256 amount)
        external
        view
        virtual
        returns (uint256[] memory)
    {
        return swapStorage.calculateRemoveLiquidity(account, amount);
    }

    /**
     * @notice Calculate the amount of underlying token available to withdraw
     * when withdrawing via only single token
     * @param account the address that is withdrawing tokens
     * @param tokenAmount the amount of LP token to burn
     * @param tokenIndex index of which token will be withdrawn
     * @return availableTokenAmount calculated amount of underlying token
     * available to withdraw
     */
    function calculateRemoveLiquidityOneToken(
        address account,
        uint256 tokenAmount,
        uint8 tokenIndex
    ) external view virtual returns (uint256 availableTokenAmount) {
        return
            swapStorage.calculateWithdrawOneToken(
                account,
                tokenAmount,
                tokenIndex
            );
    }

    /**
     * @notice Calculate the fee that is applied when the given user withdraws. The withdraw fee
     * decays linearly over period of 4 weeks. For example, depositing and withdrawing right away
     * will charge you the full amount of withdraw fee. But withdrawing after 4 weeks will charge you
     * no additional fees.
     * @dev returned value should be divided by FEE_DENOMINATOR to convert to correct decimals
     * @param user address you want to calculate withdraw fee of
     * @return current withdraw fee of the user
     */
    function calculateCurrentWithdrawFee(address user)
        external
        view
        virtual
        returns (uint256)
    {
        return swapStorage.calculateCurrentWithdrawFee(user);
    }

    /**
     * @notice This function reads the accumulated amount of admin fees of the token with given index
     * @param index Index of the pooled token
     * @return admin's token balance in the token's precision
     */
    function getAdminBalance(uint256 index)
        external
        view
        virtual
        returns (uint256)
    {
        return swapStorage.getAdminBalance(index);
    }

    /*** STATE MODIFYING FUNCTIONS ***/

    /**
     * @notice Swap two tokens using this pool
     * @param tokenIndexFrom the token the user wants to swap from
     * @param tokenIndexTo the token the user wants to swap to
     * @param dx the amount of tokens the user wants to swap from
     * @param minDy the min amount the user would like to receive, or revert.
     * @param deadline latest timestamp to accept this transaction
     */
    function swap(
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx,
        uint256 minDy,
        uint256 deadline
    )
        external
        virtual
        nonReentrant
        whenNotPaused
        deadlineCheck(deadline)
        returns (uint256)
    {
        return swapStorage.swap(tokenIndexFrom, tokenIndexTo, dx, minDy);
    }

    /**
     * @notice Add liquidity to the pool with the given amounts of tokens
     * @param amounts the amounts of each token to add, in their native precision
     * @param minToMint the minimum LP tokens adding this amount of liquidity
     * should mint, otherwise revert. Handy for front-running mitigation
     * @param deadline latest timestamp to accept this transaction
     * @return amount of LP token user minted and received
     */
    function addLiquidity(
        uint256[] calldata amounts,
        uint256 minToMint,
        uint256 deadline
    )
        external
        virtual
        nonReentrant
        whenNotPaused
        deadlineCheck(deadline)
        returns (uint256)
    {
        return swapStorage.addLiquidity(amounts, minToMint);
    }

    /**
     * @notice Burn LP tokens to remove liquidity from the pool. Withdraw fee that decays linearly
     * over period of 4 weeks since last deposit will apply.
     * @dev Liquidity can always be removed, even when the pool is paused.
     * @param amount the amount of LP tokens to burn
     * @param minAmounts the minimum amounts of each token in the pool
     *        acceptable for this burn. Useful as a front-running mitigation
     * @param deadline latest timestamp to accept this transaction
     * @return amounts of tokens user received
     */
    function removeLiquidity(
        uint256 amount,
        uint256[] calldata minAmounts,
        uint256 deadline
    )
        external
        virtual
        nonReentrant
        deadlineCheck(deadline)
        returns (uint256[] memory)
    {
        return swapStorage.removeLiquidity(amount, minAmounts);
    }

    /**
     * @notice Remove liquidity from the pool all in one token. Withdraw fee that decays linearly
     * over period of 4 weeks since last deposit will apply.
     * @param tokenAmount the amount of the token you want to receive
     * @param tokenIndex the index of the token you want to receive
     * @param minAmount the minimum amount to withdraw, otherwise revert
     * @param deadline latest timestamp to accept this transaction
     * @return amount of chosen token user received
     */
    function removeLiquidityOneToken(
        uint256 tokenAmount,
        uint8 tokenIndex,
        uint256 minAmount,
        uint256 deadline
    )
        external
        virtual
        nonReentrant
        whenNotPaused
        deadlineCheck(deadline)
        returns (uint256)
    {
        return
            swapStorage.removeLiquidityOneToken(
                tokenAmount,
                tokenIndex,
                minAmount
            );
    }

    /**
     * @notice Remove liquidity from the pool, weighted differently than the
     * pool's current balances. Withdraw fee that decays linearly
     * over period of 4 weeks since last deposit will apply.
     * @param amounts how much of each token to withdraw
     * @param maxBurnAmount the max LP token provider is willing to pay to
     * remove liquidity. Useful as a front-running mitigation.
     * @param deadline latest timestamp to accept this transaction
     * @return amount of LP tokens burned
     */
    function removeLiquidityImbalance(
        uint256[] calldata amounts,
        uint256 maxBurnAmount,
        uint256 deadline
    )
        external
        virtual
        nonReentrant
        whenNotPaused
        deadlineCheck(deadline)
        returns (uint256)
    {
        return swapStorage.removeLiquidityImbalance(amounts, maxBurnAmount);
    }

    /*** ADMIN FUNCTIONS ***/

    /**
     * @notice Updates the user withdraw fee. This function can only be called by
     * the pool token. Should be used to update the withdraw fee on transfer of pool tokens.
     * Transferring your pool token will reset the 4 weeks period. If the recipient is already
     * holding some pool tokens, the withdraw fee will be discounted in respective amounts.
     * @param recipient address of the recipient of pool token
     * @param transferAmount amount of pool token to transfer
     */
    function updateUserWithdrawFee(address recipient, uint256 transferAmount)
        external
    {
        require(
            msg.sender == address(swapStorage.lpToken),
            "Only callable by pool token"
        );
        swapStorage.updateUserWithdrawFee(recipient, transferAmount);
    }

    /**
     * @notice Withdraw all admin fees to the contract owner
     */
    function withdrawAdminFees() external onlyOwner {
        swapStorage.withdrawAdminFees(owner());
    }

    /**
     * @notice Update the admin fee. Admin fee takes portion of the swap fee.
     * @param newAdminFee new admin fee to be applied on future transactions
     */
    function setAdminFee(uint256 newAdminFee) external onlyOwner {
        swapStorage.setAdminFee(newAdminFee);
    }

    /**
     * @notice Update the swap fee to be applied on swaps
     * @param newSwapFee new swap fee to be applied on future transactions
     */
    function setSwapFee(uint256 newSwapFee) external onlyOwner {
        swapStorage.setSwapFee(newSwapFee);
    }

    /**
     * @notice Update the deposit fee.
     * @param newDepositFee new deposit fee to be applied on future deposits
     */
    function setDefaultDepositFee(uint256 newDepositFee) external onlyOwner {
        swapStorage.setDefaultDepositFee(newDepositFee);
    }

    /**
     * @notice Update the withdraw fee. This fee decays linearly over 4 weeks since
     * user's last deposit.
     * @param newWithdrawFee new withdraw fee to be applied on future deposits
     */
    function setDefaultWithdrawFee(uint256 newWithdrawFee) external onlyOwner {
        swapStorage.setDefaultWithdrawFee(newWithdrawFee);
    }

    /**
     * @notice Start ramping up or down A parameter towards given futureA and futureTime
     * Checks if the change is too rapid, and commits the new A value only when it falls under
     * the limit range.
     * @param futureA the new A to ramp towards
     * @param futureTime timestamp when the new A should be reached
     */
    function rampA(uint256 futureA, uint256 futureTime) external onlyOwner {
        swapStorage.rampA(swapStorage.getAPrecise(), futureA, futureTime);
    }

    /**
     * @notice Stop ramping A immediately. Reverts if ramp A is already stopped.
     */
    function stopRampA() external onlyOwner {
        swapStorage.stopRampA(swapStorage.getAPrecise());
    }

    /**
     * @notice Update dev address by the previous dev.
     */
    function setDevAddress(address _devaddr) external onlyOwner {
        swapStorage.setDevAddress(_devaddr);
    }
}

File 20 of 23 : SwapUtils.sol
// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;

import "@openzeppelin/contracts/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "./LPToken.sol";
import "./MathUtils.sol";

/**
 * @title SwapUtils library
 * @notice A library to be used within Swap.sol. Contains functions responsible for custody and AMM functionalities.
 * @dev Contracts relying on this library must initialize SwapUtils.Swap struct then use this library
 * for SwapUtils.Swap struct. Note that this library contains both functions called by users and admins.
 * Admin functions should be protected within contracts using this library.
 */
library SwapUtils {
    using SafeERC20 for IERC20;
    using SafeMath for uint256;
    using MathUtils for uint256;

    /*** EVENTS ***/

    event TokenSwap(
        address indexed buyer,
        uint256 tokensSold,
        uint256 tokensBought,
        uint128 soldId,
        uint128 boughtId
    );
    event AddLiquidity(
        address indexed provider,
        uint256[] tokenAmounts,
        uint256[] fees,
        uint256 invariant,
        uint256 lpTokenSupply
    );
    event RemoveLiquidity(
        address indexed provider,
        uint256[] tokenAmounts,
        uint256 lpTokenSupply
    );
    event RemoveLiquidityOne(
        address indexed provider,
        uint256 lpTokenAmount,
        uint256 lpTokenSupply,
        uint256 boughtId,
        uint256 tokensBought
    );
    event RemoveLiquidityImbalance(
        address indexed provider,
        uint256[] tokenAmounts,
        uint256[] fees,
        uint256 invariant,
        uint256 lpTokenSupply
    );
    event NewAdminFee(uint256 newAdminFee);
    event NewSwapFee(uint256 newSwapFee);
    event NewWithdrawFee(uint256 newWithdrawFee);
    event NewDepositFee(uint256 newDepositFee);

    struct Swap {
        // variables around the ramp management of A,
        // the amplification coefficient * n * (n - 1)
        // see https://www.curve.fi/stableswap-paper.pdf for details
        uint256 initialA;
        uint256 futureA;
        uint256 initialATime;
        uint256 futureATime;
        // fee calculation
        uint256 swapFee;
        uint256 adminFee;
        uint256 defaultDepositFee;
        uint256 defaultWithdrawFee;
        LPToken lpToken;
        address devaddr;
        // contract references for all tokens being pooled
        IERC20[] pooledTokens;
        // multipliers for each pooled token's precision to get to POOL_PRECISION_DECIMALS
        // for example, TBTC has 18 decimals, so the multiplier should be 1. WBTC
        // has 8, so the multiplier should be 10 ** 18 / 10 ** 8 => 10 ** 10
        uint256[] tokenPrecisionMultipliers;
        // the pool balance of each token, in the token's precision
        // the contract's actual token balance might differ
        uint256[] balances;
        mapping(address => uint256) depositTimestamp;
        mapping(address => uint256) withdrawFeeMultiplier;
    }

    // Struct storing variables used in calculations in the
    // calculateWithdrawOneTokenDY function to avoid stack too deep errors
    struct CalculateWithdrawOneTokenDYInfo {
        uint256 d0;
        uint256 d1;
        uint256 newY;
        uint256 feePerToken;
        uint256 preciseA;
    }

    // Struct storing variables used in calculations in the
    // {add,remove}Liquidity functions to avoid stack too deep errors
    struct ManageLiquidityInfo {
        uint256 d0;
        uint256 d1;
        uint256 d2;
        uint256 preciseA;
        LPToken lpToken;
        uint256 totalSupply;
        uint256[] balances;
        uint256[] multipliers;
    }

    // the precision all pools tokens will be converted to
    uint8 public constant POOL_PRECISION_DECIMALS = 18;

    // the denominator used to calculate admin and LP fees. For example, an
    // LP fee might be something like tradeAmount.mul(fee).div(FEE_DENOMINATOR)
    uint256 private constant FEE_DENOMINATOR = 10**10;

    // Max swap fee is 1% or 100bps of each swap
    uint256 public constant MAX_SWAP_FEE = 10**8;

    // Max adminFee is 100% of the swapFee
    // adminFee does not add additional fee on top of swapFee
    // Instead it takes a certain % of the swapFee. Therefore it has no impact on the
    // users but only on the earnings of LPs
    uint256 public constant MAX_ADMIN_FEE = 10**10;

    // Max withdrawFee is 1% of the value withdrawn
    // Fee will be redistributed to the LPs in the pool, rewarding
    // long term providers.
    uint256 public constant MAX_WITHDRAW_FEE = 10**8;

    // Max depositFee is 1% of the value deposited
    uint256 public constant MAX_DEPOSIT_FEE = 10**8;

    // Constant value used as max loop limit
    uint256 private constant MAX_LOOP_LIMIT = 256;

    // Constant values used in ramping A calculations
    uint256 public constant A_PRECISION = 100;

    /*** VIEW & PURE FUNCTIONS ***/

    /**
     * @notice Return A, the amplification coefficient * n * (n - 1)
     * @dev See the StableSwap paper for details
     * @param self Swap struct to read from
     * @return A parameter
     */
    function getA(Swap storage self) external view returns (uint256) {
        return getAPrecise(self).div(A_PRECISION);
    }

    /**
     * @notice Return A in its raw precision
     * @dev See the StableSwap paper for details
     * @param self Swap struct to read from
     * @return A parameter in its raw precision form
     */
    function getAPrecise(Swap storage self) public view returns (uint256) {
        uint256 t1 = self.futureATime; // time when ramp is finished
        uint256 a1 = self.futureA; // final A value when ramp is finished

        if (block.timestamp < t1) {
            uint256 t0 = self.initialATime; // time when ramp is started
            uint256 a0 = self.initialA; // initial A value when ramp is started
            if (a1 > a0) {
                // a0 + (a1 - a0) * (block.timestamp - t0) / (t1 - t0)
                return
                    a0.add(
                        a1.sub(a0).mul(block.timestamp.sub(t0)).div(t1.sub(t0))
                    );
            } else {
                // a0 - (a0 - a1) * (block.timestamp - t0) / (t1 - t0)
                return
                    a0.sub(
                        a0.sub(a1).mul(block.timestamp.sub(t0)).div(t1.sub(t0))
                    );
            }
        } else {
            return a1;
        }
    }

    /**
     * @notice Retrieves the timestamp of last deposit made by the given address
     * @param self Swap struct to read from
     * @return timestamp of last deposit
     */
    function getDepositTimestamp(Swap storage self, address user)
        external
        view
        returns (uint256)
    {
        return self.depositTimestamp[user];
    }

    /**
     * @notice Calculate the dy, the amount of selected token that user receives and
     * the fee of withdrawing in one token
     * @param account the address that is withdrawing
     * @param tokenAmount the amount to withdraw in the pool's precision
     * @param tokenIndex which token will be withdrawn
     * @param self Swap struct to read from
     * @return the amount of token user will receive
     */
    function calculateWithdrawOneToken(
        Swap storage self,
        address account,
        uint256 tokenAmount,
        uint8 tokenIndex
    ) external view returns (uint256) {
        (uint256 availableTokenAmount, ) =
            _calculateWithdrawOneToken(
                self,
                account,
                tokenAmount,
                tokenIndex,
                self.lpToken.totalSupply()
            );
        return availableTokenAmount;
    }

    function _calculateWithdrawOneToken(
        Swap storage self,
        address account,
        uint256 tokenAmount,
        uint8 tokenIndex,
        uint256 totalSupply
    ) internal view returns (uint256, uint256) {
        uint256 dy;
        uint256 newY;
        uint256 currentY;

        (dy, newY, currentY) = calculateWithdrawOneTokenDY(
            self,
            tokenIndex,
            tokenAmount,
            totalSupply
        );

        // dy_0 (without fees)
        // dy, dy_0 - dy

        uint256 dySwapFee =
            currentY
                .sub(newY)
                .div(self.tokenPrecisionMultipliers[tokenIndex])
                .sub(dy);

        dy = dy
            .mul(
            FEE_DENOMINATOR.sub(calculateCurrentWithdrawFee(self, account))
        )
            .div(FEE_DENOMINATOR);

        return (dy, dySwapFee);
    }

    /**
     * @notice Calculate the dy of withdrawing in one token
     * @param self Swap struct to read from
     * @param tokenIndex which token will be withdrawn
     * @param tokenAmount the amount to withdraw in the pools precision
     * @return the d and the new y after withdrawing one token
     */
    function calculateWithdrawOneTokenDY(
        Swap storage self,
        uint8 tokenIndex,
        uint256 tokenAmount,
        uint256 totalSupply
    )
        internal
        view
        returns (
            uint256,
            uint256,
            uint256
        )
    {
        // Get the current D, then solve the stableswap invariant
        // y_i for D - tokenAmount
        uint256[] memory xp = _xp(self);

        require(tokenIndex < xp.length, "Token index out of range");

        CalculateWithdrawOneTokenDYInfo memory v =
            CalculateWithdrawOneTokenDYInfo(0, 0, 0, 0, 0);
        v.preciseA = getAPrecise(self);
        v.d0 = getD(xp, v.preciseA);
        v.d1 = v.d0.sub(tokenAmount.mul(v.d0).div(totalSupply));

        require(tokenAmount <= xp[tokenIndex], "Withdraw exceeds available");

        v.newY = getYD(v.preciseA, tokenIndex, xp, v.d1);

        uint256[] memory xpReduced = new uint256[](xp.length);

        v.feePerToken = _feePerToken(self.swapFee, xp.length);
        for (uint256 i = 0; i < xp.length; i++) {
            uint256 xpi = xp[i];
            // if i == tokenIndex, dxExpected = xp[i] * d1 / d0 - newY
            // else dxExpected = xp[i] - (xp[i] * d1 / d0)
            // xpReduced[i] -= dxExpected * fee / FEE_DENOMINATOR
            xpReduced[i] = xpi.sub(
                (
                    (i == tokenIndex)
                        ? xpi.mul(v.d1).div(v.d0).sub(v.newY)
                        : xpi.sub(xpi.mul(v.d1).div(v.d0))
                )
                    .mul(v.feePerToken)
                    .div(FEE_DENOMINATOR)
            );
        }

        uint256 dy =
            xpReduced[tokenIndex].sub(
                getYD(v.preciseA, tokenIndex, xpReduced, v.d1)
            );
        dy = dy.sub(1).div(self.tokenPrecisionMultipliers[tokenIndex]);

        return (dy, v.newY, xp[tokenIndex]);
    }

    /**
     * @notice Calculate the price of a token in the pool with given
     * precision-adjusted balances and a particular D.
     *
     * @dev This is accomplished via solving the invariant iteratively.
     * See the StableSwap paper and Curve.fi implementation for further details.
     *
     * x_1**2 + x1 * (sum' - (A*n**n - 1) * D / (A * n**n)) = D ** (n + 1) / (n ** (2 * n) * prod' * A)
     * x_1**2 + b*x_1 = c
     * x_1 = (x_1**2 + c) / (2*x_1 + b)
     *
     * @param a the amplification coefficient * n * (n - 1). See the StableSwap paper for details.
     * @param tokenIndex Index of token we are calculating for.
     * @param xp a precision-adjusted set of pool balances. Array should be
     * the same cardinality as the pool.
     * @param d the stableswap invariant
     * @return the price of the token, in the same precision as in xp
     */
    function getYD(
        uint256 a,
        uint8 tokenIndex,
        uint256[] memory xp,
        uint256 d
    ) internal pure returns (uint256) {
        uint256 numTokens = xp.length;
        require(tokenIndex < numTokens, "Token not found");

        uint256 c = d;
        uint256 s;
        uint256 nA = a.mul(numTokens);

        for (uint256 i = 0; i < numTokens; i++) {
            if (i != tokenIndex) {
                s = s.add(xp[i]);
                c = c.mul(d).div(xp[i].mul(numTokens));
                // If we were to protect the division loss we would have to keep the denominator separate
                // and divide at the end. However this leads to overflow with large numTokens or/and D.
                // c = c * D * D * D * ... overflow!
            }
        }
        c = c.mul(d).mul(A_PRECISION).div(nA.mul(numTokens));

        uint256 b = s.add(d.mul(A_PRECISION).div(nA));
        uint256 yPrev;
        uint256 y = d;
        for (uint256 i = 0; i < MAX_LOOP_LIMIT; i++) {
            yPrev = y;
            y = y.mul(y).add(c).div(y.mul(2).add(b).sub(d));
            if (y.within1(yPrev)) {
                return y;
            }
        }
        revert("Approximation did not converge");
    }

    /**
     * @notice Get D, the StableSwap invariant, based on a set of balances and a particular A.
     * @param xp a precision-adjusted set of pool balances. Array should be the same cardinality
     * as the pool.
     * @param a the amplification coefficient * n * (n - 1) in A_PRECISION.
     * See the StableSwap paper for details
     * @return the invariant, at the precision of the pool
     */
    function getD(uint256[] memory xp, uint256 a)
        internal
        pure
        returns (uint256)
    {
        uint256 numTokens = xp.length;
        uint256 s;
        for (uint256 i = 0; i < numTokens; i++) {
            s = s.add(xp[i]);
        }
        if (s == 0) {
            return 0;
        }

        uint256 prevD;
        uint256 d = s;
        uint256 nA = a.mul(numTokens);

        for (uint256 i = 0; i < MAX_LOOP_LIMIT; i++) {
            uint256 dP = d;
            for (uint256 j = 0; j < numTokens; j++) {
                dP = dP.mul(d).div(xp[j].mul(numTokens));
                // If we were to protect the division loss we would have to keep the denominator separate
                // and divide at the end. However this leads to overflow with large numTokens or/and D.
                // dP = dP * D * D * D * ... overflow!
            }
            prevD = d;
            d = nA.mul(s).div(A_PRECISION).add(dP.mul(numTokens)).mul(d).div(
                nA.sub(A_PRECISION).mul(d).div(A_PRECISION).add(
                    numTokens.add(1).mul(dP)
                )
            );
            if (d.within1(prevD)) {
                return d;
            }
        }

        // Convergence should occur in 4 loops or less. If this is reached, there may be something wrong
        // with the pool. If this were to occur repeatedly, LPs should withdraw via `removeLiquidity()`
        // function which does not rely on D.
        revert("D does not converge");
    }

    /**
     * @notice Given a set of balances and precision multipliers, return the
     * precision-adjusted balances.
     *
     * @param balances an array of token balances, in their native precisions.
     * These should generally correspond with pooled tokens.
     *
     * @param precisionMultipliers an array of multipliers, corresponding to
     * the amounts in the balances array. When multiplied together they
     * should yield amounts at the pool's precision.
     *
     * @return an array of amounts "scaled" to the pool's precision
     */
    function _xp(
        uint256[] memory balances,
        uint256[] memory precisionMultipliers
    ) internal pure returns (uint256[] memory) {
        uint256 numTokens = balances.length;
        require(
            numTokens == precisionMultipliers.length,
            "Balances must match multipliers"
        );
        uint256[] memory xp = new uint256[](numTokens);
        for (uint256 i = 0; i < numTokens; i++) {
            xp[i] = balances[i].mul(precisionMultipliers[i]);
        }
        return xp;
    }

    /**
     * @notice Return the precision-adjusted balances of all tokens in the pool
     * @param self Swap struct to read from
     * @return the pool balances "scaled" to the pool's precision, allowing
     * them to be more easily compared.
     */
    function _xp(Swap storage self) internal view returns (uint256[] memory) {
        return _xp(self.balances, self.tokenPrecisionMultipliers);
    }

    /**
     * @notice Get the virtual price, to help calculate profit
     * @param self Swap struct to read from
     * @return the virtual price, scaled to precision of POOL_PRECISION_DECIMALS
     */
    function getVirtualPrice(Swap storage self)
        external
        view
        returns (uint256)
    {
        uint256 d = getD(_xp(self), getAPrecise(self));
        ERC20 lpToken = self.lpToken;
        uint256 supply = lpToken.totalSupply();
        if (supply > 0) {
            return d.mul(10**uint256(lpToken.decimals())).div(supply);
        }
        return 0;
    }

    /**
     * @notice Calculate the new balances of the tokens given the indexes of the token
     * that is swapped from (FROM) and the token that is swapped to (TO).
     * This function is used as a helper function to calculate how much TO token
     * the user should receive on swap.
     *
     * @param preciseA precise form of amplification coefficient
     * @param tokenIndexFrom index of FROM token
     * @param tokenIndexTo index of TO token
     * @param x the new total amount of FROM token
     * @param xp balances of the tokens in the pool
     * @return the amount of TO token that should remain in the pool
     */
    function getY(
        uint256 preciseA,
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 x,
        uint256[] memory xp
    ) internal pure returns (uint256) {
        uint256 numTokens = xp.length;
        require(
            tokenIndexFrom != tokenIndexTo,
            "Can't compare token to itself"
        );
        require(
            tokenIndexFrom < numTokens && tokenIndexTo < numTokens,
            "Tokens must be in pool"
        );

        uint256 d = getD(xp, preciseA);
        uint256 c = d;
        uint256 s;
        uint256 nA = numTokens.mul(preciseA);

        uint256 _x;
        for (uint256 i = 0; i < numTokens; i++) {
            if (i == tokenIndexFrom) {
                _x = x;
            } else if (i != tokenIndexTo) {
                _x = xp[i];
            } else {
                continue;
            }
            s = s.add(_x);
            c = c.mul(d).div(_x.mul(numTokens));
            // If we were to protect the division loss we would have to keep the denominator separate
            // and divide at the end. However this leads to overflow with large numTokens or/and D.
            // c = c * D * D * D * ... overflow!
        }
        c = c.mul(d).mul(A_PRECISION).div(nA.mul(numTokens));
        uint256 b = s.add(d.mul(A_PRECISION).div(nA));
        uint256 yPrev;
        uint256 y = d;

        // iterative approximation
        for (uint256 i = 0; i < MAX_LOOP_LIMIT; i++) {
            yPrev = y;
            y = y.mul(y).add(c).div(y.mul(2).add(b).sub(d));
            if (y.within1(yPrev)) {
                return y;
            }
        }
        revert("Approximation did not converge");
    }

    /**
     * @notice Externally calculates a swap between two tokens.
     * @param self Swap struct to read from
     * @param tokenIndexFrom the token to sell
     * @param tokenIndexTo the token to buy
     * @param dx the number of tokens to sell. If the token charges a fee on transfers,
     * use the amount that gets transferred after the fee.
     * @return dy the number of tokens the user will get
     */
    function calculateSwap(
        Swap storage self,
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx
    ) external view returns (uint256 dy) {
        (dy, ) = _calculateSwap(
            self,
            tokenIndexFrom,
            tokenIndexTo,
            dx,
            self.balances
        );
    }

    /**
     * @notice Internally calculates a swap between two tokens.
     *
     * @dev The caller is expected to transfer the actual amounts (dx and dy)
     * using the token contracts.
     *
     * @param self Swap struct to read from
     * @param tokenIndexFrom the token to sell
     * @param tokenIndexTo the token to buy
     * @param dx the number of tokens to sell. If the token charges a fee on transfers,
     * use the amount that gets transferred after the fee.
     * @return dy the number of tokens the user will get
     * @return dyFee the associated fee
     */
    function _calculateSwap(
        Swap storage self,
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx,
        uint256[] memory balances
    ) internal view returns (uint256 dy, uint256 dyFee) {
        uint256[] memory multipliers = self.tokenPrecisionMultipliers;
        uint256[] memory xp = _xp(balances, multipliers);
        require(
            tokenIndexFrom < xp.length && tokenIndexTo < xp.length,
            "Token index out of range"
        );
        uint256 x = dx.mul(multipliers[tokenIndexFrom]).add(xp[tokenIndexFrom]);
        uint256 y =
            getY(getAPrecise(self), tokenIndexFrom, tokenIndexTo, x, xp);
        dy = xp[tokenIndexTo].sub(y).sub(1);
        dyFee = dy.mul(self.swapFee).div(FEE_DENOMINATOR);
        dy = dy.sub(dyFee).div(multipliers[tokenIndexTo]);
    }

    /**
     * @notice A simple method to calculate amount of each underlying
     * tokens that is returned upon burning given amount of
     * LP tokens
     *
     * @param account the address that is removing liquidity. required for withdraw fee calculation
     * @param amount the amount of LP tokens that would to be burned on
     * withdrawal
     * @return array of amounts of tokens user will receive
     */
    function calculateRemoveLiquidity(
        Swap storage self,
        address account,
        uint256 amount
    ) external view returns (uint256[] memory) {
        return
            _calculateRemoveLiquidity(
                self,
                self.balances,
                account,
                amount,
                self.lpToken.totalSupply()
            );
    }

    function _calculateRemoveLiquidity(
        Swap storage self,
        uint256[] memory balances,
        address account,
        uint256 amount,
        uint256 totalSupply
    ) internal view returns (uint256[] memory) {
        require(amount <= totalSupply, "Cannot exceed total supply");

        uint256 feeAdjustedAmount =
            amount
                .mul(
                FEE_DENOMINATOR.sub(calculateCurrentWithdrawFee(self, account))
            )
                .div(FEE_DENOMINATOR);

        uint256[] memory amounts = new uint256[](balances.length);

        for (uint256 i = 0; i < balances.length; i++) {
            amounts[i] = balances[i].mul(feeAdjustedAmount).div(totalSupply);
        }
        return amounts;
    }

    /**
     * @notice Calculate the fee that is applied when the given user withdraws.
     * Withdraw fee decays linearly over 4 weeks.
     * @param user address you want to calculate withdraw fee of
     * @return current withdraw fee of the user
     */
    function calculateCurrentWithdrawFee(Swap storage self, address user)
        public
        view
        returns (uint256)
    {
        uint256 endTime = self.depositTimestamp[user].add(4 weeks);
        if (endTime > block.timestamp) {
            uint256 timeLeftover = endTime.sub(block.timestamp);
            return
                self
                    .defaultWithdrawFee
                    .mul(self.withdrawFeeMultiplier[user])
                    .mul(timeLeftover)
                    .div(4 weeks)
                    .div(FEE_DENOMINATOR);
        }
        return 0;
    }

    /**
     * @notice A simple method to calculate prices from deposits or
     * withdrawals, excluding fees but including slippage. This is
     * helpful as an input into the various "min" parameters on calls
     * to fight front-running
     *
     * @dev This shouldn't be used outside frontends for user estimates.
     *
     * @param self Swap struct to read from
     * @param account address of the account depositing or withdrawing tokens
     * @param amounts an array of token amounts to deposit or withdrawal,
     * corresponding to pooledTokens. The amount should be in each
     * pooled token's native precision. If a token charges a fee on transfers,
     * use the amount that gets transferred after the fee.
     * @param deposit whether this is a deposit or a withdrawal
     * @return if deposit was true, total amount of lp token that will be minted and if
     * deposit was false, total amount of lp token that will be burned
     */
    function calculateTokenAmount(
        Swap storage self,
        address account,
        uint256[] calldata amounts,
        bool deposit
    ) external view returns (uint256) {
        uint256 a = getAPrecise(self);
        uint256[] memory balances = self.balances;
        uint256[] memory multipliers = self.tokenPrecisionMultipliers;

        uint256 d0 = getD(_xp(balances, multipliers), a);
        for (uint256 i = 0; i < balances.length; i++) {
            if (deposit) {
                balances[i] = balances[i].add(amounts[i]);
            } else {
                balances[i] = balances[i].sub(
                    amounts[i],
                    "Cannot withdraw more than available"
                );
            }
        }
        uint256 d1 = getD(_xp(balances, multipliers), a);
        uint256 totalSupply = self.lpToken.totalSupply();

        if (deposit) {
            return d1.sub(d0).mul(totalSupply).div(d0);
        } else {
            return
                d0.sub(d1).mul(totalSupply).div(d0).mul(FEE_DENOMINATOR).div(
                    FEE_DENOMINATOR.sub(
                        calculateCurrentWithdrawFee(self, account)
                    )
                );
        }
    }

    /**
     * @notice return accumulated amount of admin fees of the token with given index
     * @param self Swap struct to read from
     * @param index Index of the pooled token
     * @return admin balance in the token's precision
     */
    function getAdminBalance(Swap storage self, uint256 index)
        external
        view
        returns (uint256)
    {
        require(index < self.pooledTokens.length, "Token index out of range");
        return
            self.pooledTokens[index].balanceOf(address(this)).sub(
                self.balances[index]
            );
    }

    /**
     * @notice internal helper function to calculate fee per token multiplier used in
     * swap fee calculations
     * @param swapFee swap fee for the tokens
     * @param numTokens number of tokens pooled
     */
    function _feePerToken(uint256 swapFee, uint256 numTokens)
        internal
        pure
        returns (uint256)
    {
        return swapFee.mul(numTokens).div(numTokens.sub(1).mul(4));
    }

    /*** STATE MODIFYING FUNCTIONS ***/

    /**
     * @notice swap two tokens in the pool
     * @param self Swap struct to read from and write to
     * @param tokenIndexFrom the token the user wants to sell
     * @param tokenIndexTo the token the user wants to buy
     * @param dx the amount of tokens the user wants to sell
     * @param minDy the min amount the user would like to receive, or revert.
     * @return amount of token user received on swap
     */
    function swap(
        Swap storage self,
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx,
        uint256 minDy
    ) external returns (uint256) {
        {
            IERC20 tokenFrom = self.pooledTokens[tokenIndexFrom];
            require(
                dx <= tokenFrom.balanceOf(msg.sender),
                "Cannot swap more than you own"
            );
            // Transfer tokens first to see if a fee was charged on transfer
            uint256 beforeBalance = tokenFrom.balanceOf(address(this));
            tokenFrom.safeTransferFrom(msg.sender, address(this), dx);

            // Use the actual transferred amount for AMM math
            dx = tokenFrom.balanceOf(address(this)).sub(beforeBalance);
        }

        uint256 dy;
        uint256 dyFee;
        uint256[] memory balances = self.balances;
        (dy, dyFee) = _calculateSwap(
            self,
            tokenIndexFrom,
            tokenIndexTo,
            dx,
            balances
        );
        require(dy >= minDy, "Swap didn't result in min tokens");

        uint256 dyAdminFee =
            dyFee.mul(self.adminFee).div(FEE_DENOMINATOR).div(
                self.tokenPrecisionMultipliers[tokenIndexTo]
            );

        self.balances[tokenIndexFrom] = balances[tokenIndexFrom].add(dx);
        self.balances[tokenIndexTo] = balances[tokenIndexTo].sub(dy).sub(
            dyAdminFee
        );

        self.pooledTokens[tokenIndexTo].safeTransfer(msg.sender, dy);

        emit TokenSwap(msg.sender, dx, dy, tokenIndexFrom, tokenIndexTo);

        return dy;
    }

    /**
     * @notice Add liquidity to the pool
     * @param self Swap struct to read from and write to
     * @param amounts the amounts of each token to add, in their native precision
     * @param minToMint the minimum LP tokens adding this amount of liquidity
     * should mint, otherwise revert. Handy for front-running mitigation
     * allowed addresses. If the pool is not in the guarded launch phase, this parameter will be ignored.
     * @return amount of LP token user received
     */
    function addLiquidity(
        Swap storage self,
        uint256[] memory amounts,
        uint256 minToMint
    ) external returns (uint256) {
        IERC20[] memory pooledTokens = self.pooledTokens;
        require(
            amounts.length == pooledTokens.length,
            "Amounts must match pooled tokens"
        );

        // current state
        ManageLiquidityInfo memory v =
            ManageLiquidityInfo(
                0,
                0,
                0,
                getAPrecise(self),
                self.lpToken,
                0,
                self.balances,
                self.tokenPrecisionMultipliers
            );
        v.totalSupply = v.lpToken.totalSupply();

        if (v.totalSupply != 0) {
            v.d0 = getD(_xp(v.balances, v.multipliers), v.preciseA);
        }

        uint256[] memory newBalances = new uint256[](pooledTokens.length);

        for (uint256 i = 0; i < pooledTokens.length; i++) {
            require(
                v.totalSupply != 0 || amounts[i] > 0,
                "Must supply all tokens in pool"
            );

            // Transfer tokens first to see if a fee was charged on transfer
            if (amounts[i] != 0) {
                uint256 beforeBalance =
                    pooledTokens[i].balanceOf(address(this));
                pooledTokens[i].safeTransferFrom(
                    msg.sender,
                    address(this),
                    amounts[i]
                );

                // Update the amounts[] with actual transfer amount
                amounts[i] = pooledTokens[i].balanceOf(address(this)).sub(
                    beforeBalance
                );
            }

            newBalances[i] = v.balances[i].add(amounts[i]);
        }

        // invariant after change
        v.d1 = getD(_xp(newBalances, v.multipliers), v.preciseA);
        require(v.d1 > v.d0, "D should increase");

        // updated to reflect fees and calculate the user's LP tokens
        v.d2 = v.d1;
        uint256[] memory fees = new uint256[](pooledTokens.length);

        if (v.totalSupply != 0) {
            uint256 feePerToken =
                _feePerToken(self.swapFee, pooledTokens.length);
            for (uint256 i = 0; i < pooledTokens.length; i++) {
                uint256 idealBalance = v.d1.mul(v.balances[i]).div(v.d0);
                fees[i] = feePerToken
                    .mul(idealBalance.difference(newBalances[i]))
                    .div(FEE_DENOMINATOR);
                self.balances[i] = newBalances[i].sub(
                    fees[i].mul(self.adminFee).div(FEE_DENOMINATOR)
                );
                newBalances[i] = newBalances[i].sub(fees[i]);
            }
            v.d2 = getD(_xp(newBalances, v.multipliers), v.preciseA);
        } else {
            // the initial depositor doesn't pay fees
            self.balances = newBalances;
        }

        uint256 toMint;
        uint256 toMintFee;
        uint256 toMintUser;
        if (v.totalSupply == 0) {
            toMint = v.d1;
        } else {
            toMint = v.d2.sub(v.d0).mul(v.totalSupply).div(v.d0);
        }

        require(toMint >= minToMint, "Couldn't mint min requested");

        // if deposit fee is none, mint full amount
        if (self.defaultDepositFee == 0) {
            self.lpToken.mint(msg.sender, toMint);
        } else {
            // mint the user's LP tokens minus the deposit fee
            toMintFee = toMint.mul(self.defaultDepositFee).div(FEE_DENOMINATOR);
            toMintUser = toMint.sub(toMintFee);
            self.lpToken.mint(self.devaddr, toMintFee);
            self.lpToken.mint(msg.sender, toMintUser);
        }

        emit AddLiquidity(
            msg.sender,
            amounts,
            fees,
            v.d1,
            v.totalSupply.add(toMint)
        );

        return toMint;
    }

    /**
     * @notice Update the withdraw fee for `user`. If the user is currently
     * not providing liquidity in the pool, sets to default value. If not, recalculate
     * the starting withdraw fee based on the last deposit's time & amount relative
     * to the new deposit.
     *
     * @param self Swap struct to read from and write to
     * @param user address of the user depositing tokens
     * @param toMint amount of pool tokens to be minted
     */
    function updateUserWithdrawFee(
        Swap storage self,
        address user,
        uint256 toMint
    ) public {
        // If token is transferred to address 0 (or burned), don't update the fee.
        if (user == address(0)) {
            return;
        }
        if (self.defaultWithdrawFee == 0) {
            // If current fee is set to 0%, set multiplier to FEE_DENOMINATOR
            self.withdrawFeeMultiplier[user] = FEE_DENOMINATOR;
        } else {
            // Otherwise, calculate appropriate discount based on last deposit amount
            uint256 currentFee = calculateCurrentWithdrawFee(self, user);
            uint256 currentBalance = self.lpToken.balanceOf(user);

            // ((currentBalance * currentFee) + (toMint * defaultWithdrawFee)) * FEE_DENOMINATOR /
            // ((toMint + currentBalance) * defaultWithdrawFee)
            self.withdrawFeeMultiplier[user] = currentBalance
                .mul(currentFee)
                .add(toMint.mul(self.defaultWithdrawFee))
                .mul(FEE_DENOMINATOR)
                .div(toMint.add(currentBalance).mul(self.defaultWithdrawFee));
        }
        self.depositTimestamp[user] = block.timestamp;
    }

    /**
     * @notice Burn LP tokens to remove liquidity from the pool.
     * @dev Liquidity can always be removed, even when the pool is paused.
     * @param self Swap struct to read from and write to
     * @param amount the amount of LP tokens to burn
     * @param minAmounts the minimum amounts of each token in the pool
     * acceptable for this burn. Useful as a front-running mitigation
     * @return amounts of tokens the user received
     */
    function removeLiquidity(
        Swap storage self,
        uint256 amount,
        uint256[] calldata minAmounts
    ) external returns (uint256[] memory) {
        LPToken lpToken = self.lpToken;
        IERC20[] memory pooledTokens = self.pooledTokens;
        require(amount <= lpToken.balanceOf(msg.sender), ">LP.balanceOf");
        require(
            minAmounts.length == pooledTokens.length,
            "minAmounts must match poolTokens"
        );

        uint256[] memory balances = self.balances;
        uint256 totalSupply = lpToken.totalSupply();

        uint256[] memory amounts =
            _calculateRemoveLiquidity(
                self,
                balances,
                msg.sender,
                amount,
                totalSupply
            );

        for (uint256 i = 0; i < amounts.length; i++) {
            require(amounts[i] >= minAmounts[i], "amounts[i] < minAmounts[i]");
            self.balances[i] = balances[i].sub(amounts[i]);
            pooledTokens[i].safeTransfer(msg.sender, amounts[i]);
        }

        lpToken.burnFrom(msg.sender, amount);

        emit RemoveLiquidity(msg.sender, amounts, totalSupply.sub(amount));

        return amounts;
    }

    /**
     * @notice Remove liquidity from the pool all in one token.
     * @param self Swap struct to read from and write to
     * @param tokenAmount the amount of the lp tokens to burn
     * @param tokenIndex the index of the token you want to receive
     * @param minAmount the minimum amount to withdraw, otherwise revert
     * @return amount chosen token that user received
     */
    function removeLiquidityOneToken(
        Swap storage self,
        uint256 tokenAmount,
        uint8 tokenIndex,
        uint256 minAmount
    ) external returns (uint256) {
        LPToken lpToken = self.lpToken;
        IERC20[] memory pooledTokens = self.pooledTokens;

        require(tokenAmount <= lpToken.balanceOf(msg.sender), ">LP.balanceOf");
        require(tokenIndex < pooledTokens.length, "Token not found");

        uint256 totalSupply = lpToken.totalSupply();

        (uint256 dy, uint256 dyFee) =
            _calculateWithdrawOneToken(
                self,
                msg.sender,
                tokenAmount,
                tokenIndex,
                totalSupply
            );

        require(dy >= minAmount, "dy < minAmount");

        self.balances[tokenIndex] = self.balances[tokenIndex].sub(
            dy.add(dyFee.mul(self.adminFee).div(FEE_DENOMINATOR))
        );
        lpToken.burnFrom(msg.sender, tokenAmount);
        pooledTokens[tokenIndex].safeTransfer(msg.sender, dy);

        emit RemoveLiquidityOne(
            msg.sender,
            tokenAmount,
            totalSupply,
            tokenIndex,
            dy
        );

        return dy;
    }

    /**
     * @notice Remove liquidity from the pool, weighted differently than the
     * pool's current balances.
     *
     * @param self Swap struct to read from and write to
     * @param amounts how much of each token to withdraw
     * @param maxBurnAmount the max LP token provider is willing to pay to
     * remove liquidity. Useful as a front-running mitigation.
     * @return actual amount of LP tokens burned in the withdrawal
     */
    function removeLiquidityImbalance(
        Swap storage self,
        uint256[] memory amounts,
        uint256 maxBurnAmount
    ) public returns (uint256) {
        ManageLiquidityInfo memory v =
            ManageLiquidityInfo(
                0,
                0,
                0,
                getAPrecise(self),
                self.lpToken,
                0,
                self.balances,
                self.tokenPrecisionMultipliers
            );
        v.totalSupply = v.lpToken.totalSupply();

        IERC20[] memory pooledTokens = self.pooledTokens;

        require(
            amounts.length == pooledTokens.length,
            "Amounts should match pool tokens"
        );

        require(
            maxBurnAmount <= v.lpToken.balanceOf(msg.sender) &&
                maxBurnAmount != 0,
            ">LP.balanceOf"
        );

        uint256 feePerToken = _feePerToken(self.swapFee, pooledTokens.length);
        uint256[] memory fees = new uint256[](pooledTokens.length);
        {
            uint256[] memory balances1 = new uint256[](pooledTokens.length);
            v.d0 = getD(_xp(v.balances, v.multipliers), v.preciseA);
            for (uint256 i = 0; i < pooledTokens.length; i++) {
                balances1[i] = v.balances[i].sub(
                    amounts[i],
                    "Cannot withdraw more than available"
                );
            }
            v.d1 = getD(_xp(balances1, v.multipliers), v.preciseA);

            for (uint256 i = 0; i < pooledTokens.length; i++) {
                uint256 idealBalance = v.d1.mul(v.balances[i]).div(v.d0);
                uint256 difference = idealBalance.difference(balances1[i]);
                fees[i] = feePerToken.mul(difference).div(FEE_DENOMINATOR);
                self.balances[i] = balances1[i].sub(
                    fees[i].mul(self.adminFee).div(FEE_DENOMINATOR)
                );
                balances1[i] = balances1[i].sub(fees[i]);
            }

            v.d2 = getD(_xp(balances1, v.multipliers), v.preciseA);
        }
        uint256 tokenAmount = v.d0.sub(v.d2).mul(v.totalSupply).div(v.d0);
        require(tokenAmount != 0, "Burnt amount cannot be zero");
        tokenAmount = tokenAmount.add(1).mul(FEE_DENOMINATOR).div(
            FEE_DENOMINATOR.sub(calculateCurrentWithdrawFee(self, msg.sender))
        );

        require(tokenAmount <= maxBurnAmount, "tokenAmount > maxBurnAmount");

        v.lpToken.burnFrom(msg.sender, tokenAmount);

        for (uint256 i = 0; i < pooledTokens.length; i++) {
            pooledTokens[i].safeTransfer(msg.sender, amounts[i]);
        }

        emit RemoveLiquidityImbalance(
            msg.sender,
            amounts,
            fees,
            v.d1,
            v.totalSupply.sub(tokenAmount)
        );

        return tokenAmount;
    }

    /**
     * @notice withdraw all admin fees to a given address
     * @param self Swap struct to withdraw fees from
     * @param to Address to send the fees to
     */
    function withdrawAdminFees(Swap storage self, address to) external {
        IERC20[] memory pooledTokens = self.pooledTokens;
        for (uint256 i = 0; i < pooledTokens.length; i++) {
            IERC20 token = pooledTokens[i];
            uint256 balance =
                token.balanceOf(address(this)).sub(self.balances[i]);
            if (balance != 0) {
                token.safeTransfer(to, balance);
            }
        }
    }

    /**
     * @notice Sets the admin fee
     * @dev adminFee cannot be higher than 100% of the swap fee
     * @param self Swap struct to update
     * @param newAdminFee new admin fee to be applied on future transactions
     */
    function setAdminFee(Swap storage self, uint256 newAdminFee) external {
        require(newAdminFee <= MAX_ADMIN_FEE, "Fee is too high");
        self.adminFee = newAdminFee;

        emit NewAdminFee(newAdminFee);
    }

    /**
     * @notice update the swap fee
     * @dev fee cannot be higher than 1% of each swap
     * @param self Swap struct to update
     * @param newSwapFee new swap fee to be applied on future transactions
     */
    function setSwapFee(Swap storage self, uint256 newSwapFee) external {
        require(newSwapFee <= MAX_SWAP_FEE, "Fee is too high");
        self.swapFee = newSwapFee;

        emit NewSwapFee(newSwapFee);
    }

    /**
     * @notice update the default withdraw fee. This also affects deposits made in the past as well.
     * @param self Swap struct to update
     * @param newWithdrawFee new withdraw fee to be applied
     */
    function setDefaultWithdrawFee(Swap storage self, uint256 newWithdrawFee)
        external
    {
        require(newWithdrawFee <= MAX_WITHDRAW_FEE, "Fee is too high");
        self.defaultWithdrawFee = newWithdrawFee;

        emit NewWithdrawFee(newWithdrawFee);
    }

    /**
     * @notice update the default deposit fee.
     * @param self Swap struct to update
     * @param newDepositFee new deposit fee to be applied
     */
    function setDefaultDepositFee(Swap storage self, uint256 newDepositFee)
        external
    {
        require(newDepositFee <= MAX_DEPOSIT_FEE, "Fee is too high");
        self.defaultDepositFee = newDepositFee;

        emit NewDepositFee(newDepositFee);
    }

    /**
     * @notice updates the dev address
     * @param self Swap struct to update
     * @param _devaddr new dev address
     */

    function setDevAddress(Swap storage self, address _devaddr) public {
        require(msg.sender == self.devaddr, "dev: wut?");
        require(msg.sender != address(0), "invalid address");
        self.devaddr = _devaddr;
    }
}

File 21 of 23 : ISwap.sol
// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";

interface ISwap {
    // pool data view functions
    function getA() external view returns (uint256);

    function getToken(uint8 index) external view returns (IERC20);

    function getTokenIndex(address tokenAddress) external view returns (uint8);

    function getTokenBalance(uint8 index) external view returns (uint256);

    function getVirtualPrice() external view returns (uint256);

    // min return calculation functions
    function calculateSwap(
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx
    ) external view returns (uint256);

    function calculateTokenAmount(
        address account,
        uint256[] calldata amounts,
        bool deposit
    ) external view returns (uint256);

    function calculateRemoveLiquidity(address account, uint256 amount)
        external
        view
        returns (uint256[] memory);

    function calculateRemoveLiquidityOneToken(
        address account,
        uint256 tokenAmount,
        uint8 tokenIndex
    ) external view returns (uint256 availableTokenAmount);

    // state modifying functions
    function initialize(
        IERC20[] memory pooledTokens,
        uint8[] memory decimals,
        string memory lpTokenName,
        string memory lpTokenSymbol,
        uint256 a,
        uint256 fee,
        uint256 adminFee,
        uint256 depositFee,
        uint256 withdrawFee,
        address devaddr
    ) external;

    function swap(
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx,
        uint256 minDy,
        uint256 deadline
    ) external returns (uint256);

    function addLiquidity(
        uint256[] calldata amounts,
        uint256 minToMint,
        uint256 deadline
    ) external returns (uint256);

    function removeLiquidity(
        uint256 amount,
        uint256[] calldata minAmounts,
        uint256 deadline
    ) external returns (uint256[] memory);

    function removeLiquidityOneToken(
        uint256 tokenAmount,
        uint8 tokenIndex,
        uint256 minAmount,
        uint256 deadline
    ) external returns (uint256);

    function removeLiquidityImbalance(
        uint256[] calldata amounts,
        uint256 maxBurnAmount,
        uint256 deadline
    ) external returns (uint256);

    // withdraw fee update function
    function updateUserWithdrawFee(address recipient, uint256 transferAmount)
        external;
}

File 22 of 23 : MetaSwap.sol
// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;

import "@openzeppelin/contracts/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "@openzeppelin/contracts-upgradeable/utils/ReentrancyGuardUpgradeable.sol";
import "../OwnerPausableUpgradeable.sol";
import "./MetaSwapUtils.sol";
import "../MathUtils.sol";
import "../Swap.sol";

/**
 * @title MetaSwap - A StableSwap implementation in solidity.
 * @notice This contract is responsible for custody of closely pegged assets (eg. group of stablecoins)
 * and automatic market making system. Users become an LP (Liquidity Provider) by depositing their tokens
 * in desired ratios for an exchange of the pool token that represents their share of the pool.
 * Users can burn pool tokens and withdraw their share of token(s).
 *
 * Each time a swap between the pooled tokens happens, a set fee incurs which effectively gets
 * distributed to the LPs.
 *
 * In case of emergencies, admin can pause additional deposits, swaps, or single-asset withdraws - which
 * stops the ratio of the tokens in the pool from changing.
 * Users can always withdraw their tokens via multi-asset withdraws.
 *
 * MetaSwap is a modified version of Swap that allows Swap's LP token to be utilized in pooling with other tokens.
 *
 * @dev Most of the logic is stored as a library `SwapUtils` for the sake of reducing contract's
 * deployment size.
 */
contract MetaSwap is Swap {
    using MetaSwapUtils for SwapUtils.Swap;

    MetaSwapUtils.MetaSwap public metaSwapStorage;

    uint256 constant MAX_UINT256 = 2**256 - 1;

    /*** EVENTS ***/

    // events replicated from SwapUtils to make the ABI easier for dumb
    // clients
    event TokenSwapUnderlying(
        address indexed buyer,
        uint256 tokensSold,
        uint256 tokensBought,
        uint128 soldId,
        uint128 boughtId
    );

    // /**
    //  * @notice Initializes this Swap contract with the given parameters.
    //  * This will also deploy the LPToken that represents users
    //  * LP position. The owner of LPToken will be this contract - which means
    //  * only this contract is allowed to mint new tokens.
    //  *
    //  * @param _pooledTokens an array of ERC20s this pool will accept
    //  * @param decimals the decimals to use for each pooled token,
    //  * eg 8 for WBTC. Cannot be larger than POOL_PRECISION_DECIMALS
    //  * @param lpTokenName the long-form name of the token to be deployed
    //  * @param lpTokenSymbol the short symbol for the token to be deployed
    //  * @param _a the amplification coefficient * n * (n - 1). See the
    //  * StableSwap paper for details
    //  * @param _fee default swap fee to be initialized with
    //  * @param _adminFee default adminFee to be initialized with
    //  * @param _withdrawFee default withdrawFee to be initialized with
    //  */
    // function initialize(
    //     IERC20[] memory _pooledTokens,
    //     uint8[] memory decimals,
    //     string memory lpTokenName,
    //     string memory lpTokenSymbol,
    //     uint256 _a,
    //     uint256 _fee,
    //     uint256 _adminFee,
    //     uint256 _depositFee,
    //     uint256 _withdrawFee,
    //     address _devaddr
    // ) public virtual override initializer {
    //     revert("use initializeMetaSwap() instead");
    // }

    /**
     * @notice Initializes this Swap contract with the given parameters.
     * This will also deploy the LPToken that represents users
     * LP position. The owner of LPToken will be this contract - which means
     * only this contract is allowed to mint new tokens.
     *
     * @param _pooledTokens an array of ERC20s this pool will accept
     * @param decimals the decimals to use for each pooled token,
     * eg 8 for WBTC. Cannot be larger than POOL_PRECISION_DECIMALS
     * @param lpTokenName the long-form name of the token to be deployed
     * @param lpTokenSymbol the short symbol for the token to be deployed
     * @param _a the amplification coefficient * n * (n - 1). See the
     * StableSwap paper for details
     * @param _fee default swap fee to be initialized with
     * @param _adminFee default adminFee to be initialized with
     * @param _depositFee default depositFee to be initialized with
     * @param _withdrawFee default withdrawFee to be initialized with
     * @param _devaddr default _devaddr to be initialized with
     */
    function initializeMetaSwap(
        IERC20[] memory _pooledTokens,
        uint8[] memory decimals,
        string memory lpTokenName,
        string memory lpTokenSymbol,
        uint256 _a,
        uint256 _fee,
        uint256 _adminFee,
        uint256 _depositFee,
        uint256 _withdrawFee,
        address _devaddr,
        ISwap baseSwap
    ) public virtual initializer {
        Swap.initialize(
            _pooledTokens,
            decimals,
            lpTokenName,
            lpTokenSymbol,
            _a,
            _fee,
            _adminFee,
            _depositFee,
            _withdrawFee,
            _devaddr
        );

        // MetaSwap initializer
        metaSwapStorage.baseSwap = baseSwap;
        metaSwapStorage.baseVirtualPrice = baseSwap.getVirtualPrice();
        metaSwapStorage.baseCacheLastUpdated = block.timestamp;
        for (uint8 i; i < 32; i++) {
            try baseSwap.getToken(i) returns (IERC20 token) {
                token.approve(address(baseSwap), MAX_UINT256);
                metaSwapStorage.baseTokens.push(token);
            } catch {
                break;
            }
        }
        _pooledTokens[_pooledTokens.length - 1].approve(
            address(baseSwap),
            MAX_UINT256
        );
    }

    /**
     * @notice Get the virtual price, to help calculate profit
     * @return the virtual price, scaled to the POOL_PRECISION_DECIMALS
     */
    function getVirtualPrice()
        external
        view
        virtual
        override
        returns (uint256)
    {
        return swapStorage.getVirtualPrice(metaSwapStorage);
    }

    /**
     * @notice Calculate amount of tokens you receive on swap
     * @param tokenIndexFrom the token the user wants to sell
     * @param tokenIndexTo the token the user wants to buy
     * @param dx the amount of tokens the user wants to sell. If the token charges
     * a fee on transfers, use the amount that gets transferred after the fee.
     * @return amount of tokens the user will receive
     */
    function calculateSwap(
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx
    ) external view virtual override returns (uint256) {
        return
            swapStorage.calculateSwap(
                metaSwapStorage,
                tokenIndexFrom,
                tokenIndexTo,
                dx
            );
    }

    /**
     * @notice Calculate amount of tokens you receive on swap. For this function,
     * the token indices are flattened out so that underlying tokens are represented.
     * @param tokenIndexFrom the token the user wants to sell
     * @param tokenIndexTo the token the user wants to buy
     * @param dx the amount of tokens the user wants to sell. If the token charges
     * a fee on transfers, use the amount that gets transferred after the fee.
     * @return amount of tokens the user will receive
     */
    function calculateSwapUnderlying(
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx
    ) external view virtual returns (uint256) {
        return
            swapStorage.calculateSwapUnderlying(
                metaSwapStorage,
                tokenIndexFrom,
                tokenIndexTo,
                dx
            );
    }

    /**
     * @notice A simple method to calculate prices from deposits or
     * withdrawals, excluding fees but including slippage. This is
     * helpful as an input into the various "min" parameters on calls
     * to fight front-running
     *
     * @dev This shouldn't be used outside frontends for user estimates.
     *
     * @param account address that is depositing or withdrawing tokens
     * @param amounts an array of token amounts to deposit or withdrawal,
     * corresponding to pooledTokens. The amount should be in each
     * pooled token's native precision. If a token charges a fee on transfers,
     * use the amount that gets transferred after the fee.
     * @param deposit whether this is a deposit or a withdrawal
     * @return token amount the user will receive
     */
    function calculateTokenAmount(
        address account,
        uint256[] calldata amounts,
        bool deposit
    ) external view virtual override returns (uint256) {
        return
            swapStorage.calculateTokenAmount(
                metaSwapStorage,
                account,
                amounts,
                deposit
            );
    }

    /**
     * @notice Calculate the amount of underlying token available to withdraw
     * when withdrawing via only single token
     * @param account the address that is withdrawing tokens
     * @param tokenAmount the amount of LP token to burn
     * @param tokenIndex index of which token will be withdrawn
     * @return availableTokenAmount calculated amount of underlying token
     * available to withdraw
     */
    function calculateRemoveLiquidityOneToken(
        address account,
        uint256 tokenAmount,
        uint8 tokenIndex
    ) external view virtual override returns (uint256) {
        return
            swapStorage.calculateWithdrawOneToken(
                metaSwapStorage,
                account,
                tokenAmount,
                tokenIndex
            );
    }

    /*** STATE MODIFYING FUNCTIONS ***/

    /**
     * @notice Swap two tokens using this pool
     * @param tokenIndexFrom the token the user wants to swap from
     * @param tokenIndexTo the token the user wants to swap to
     * @param dx the amount of tokens the user wants to swap from
     * @param minDy the min amount the user would like to receive, or revert.
     * @param deadline latest timestamp to accept this transaction
     */
    function swap(
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx,
        uint256 minDy,
        uint256 deadline
    )
        external
        virtual
        override
        nonReentrant
        whenNotPaused
        deadlineCheck(deadline)
        returns (uint256)
    {
        return
            swapStorage.swap(
                metaSwapStorage,
                tokenIndexFrom,
                tokenIndexTo,
                dx,
                minDy
            );
    }

    /**
     * @notice Swap two tokens using this pool and the base pool.
     * @param tokenIndexFrom the token the user wants to swap from
     * @param tokenIndexTo the token the user wants to swap to
     * @param dx the amount of tokens the user wants to swap from
     * @param minDy the min amount the user would like to receive, or revert.
     * @param deadline latest timestamp to accept this transaction
     */
    function swapUnderlying(
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx,
        uint256 minDy,
        uint256 deadline
    )
        external
        virtual
        nonReentrant
        whenNotPaused
        deadlineCheck(deadline)
        returns (uint256)
    {
        return
            swapStorage.swapUnderlying(
                metaSwapStorage,
                tokenIndexFrom,
                tokenIndexTo,
                dx,
                minDy
            );
    }

    /**
     * @notice Add liquidity to the pool with the given amounts of tokens
     * @param amounts the amounts of each token to add, in their native precision
     * @param minToMint the minimum LP tokens adding this amount of liquidity
     * should mint, otherwise revert. Handy for front-running mitigation
     * @param deadline latest timestamp to accept this transaction
     * @return amount of LP token user minted and received
     */
    function addLiquidity(
        uint256[] calldata amounts,
        uint256 minToMint,
        uint256 deadline
    )
        external
        virtual
        override
        nonReentrant
        whenNotPaused
        deadlineCheck(deadline)
        returns (uint256)
    {
        return swapStorage.addLiquidity(metaSwapStorage, amounts, minToMint);
    }

    /**
     * @notice Remove liquidity from the pool all in one token. Withdraw fee that decays linearly
     * over period of 4 weeks since last deposit will apply.
     * @param tokenAmount the amount of the token you want to receive
     * @param tokenIndex the index of the token you want to receive
     * @param minAmount the minimum amount to withdraw, otherwise revert
     * @param deadline latest timestamp to accept this transaction
     * @return amount of chosen token user received
     */
    function removeLiquidityOneToken(
        uint256 tokenAmount,
        uint8 tokenIndex,
        uint256 minAmount,
        uint256 deadline
    )
        external
        virtual
        override
        nonReentrant
        whenNotPaused
        deadlineCheck(deadline)
        returns (uint256)
    {
        return
            swapStorage.removeLiquidityOneToken(
                metaSwapStorage,
                tokenAmount,
                tokenIndex,
                minAmount
            );
    }

    /**
     * @notice Remove liquidity from the pool, weighted differently than the
     * pool's current balances. Withdraw fee that decays linearly
     * over period of 4 weeks since last deposit will apply.
     * @param amounts how much of each token to withdraw
     * @param maxBurnAmount the max LP token provider is willing to pay to
     * remove liquidity. Useful as a front-running mitigation.
     * @param deadline latest timestamp to accept this transaction
     * @return amount of LP tokens burned
     */
    function removeLiquidityImbalance(
        uint256[] calldata amounts,
        uint256 maxBurnAmount,
        uint256 deadline
    )
        external
        virtual
        override
        nonReentrant
        whenNotPaused
        deadlineCheck(deadline)
        returns (uint256)
    {
        return
            swapStorage.removeLiquidityImbalance(
                metaSwapStorage,
                amounts,
                maxBurnAmount
            );
    }
}

File 23 of 23 : MetaSwapUtils.sol
// SPDX-License-Identifier: MIT

pragma solidity 0.6.12;

import "@openzeppelin/contracts/math/SafeMath.sol";
import "@openzeppelin/contracts/token/ERC20/SafeERC20.sol";
import "../LPToken.sol";
import "../interfaces/ISwap.sol";
import "../MathUtils.sol";
import "../SwapUtils.sol";

/**
 * @title MetaSwapUtils library
 * @notice A library to be used within MetaSwap.sol. Contains functions responsible for custody and AMM functionalities.
 * @dev Contracts relying on this library must initialize SwapUtils.Swap struct then use this library
 * for SwapUtils.Swap struct. Note that this library contains both functions called by users and admins.
 * Admin functions should be protected within contracts using this library.
 */
library MetaSwapUtils {
    using SafeERC20 for IERC20;
    using SafeMath for uint256;
    using MathUtils for uint256;

    /*** EVENTS ***/

    event TokenSwap(
        address indexed buyer,
        uint256 tokensSold,
        uint256 tokensBought,
        uint128 soldId,
        uint128 boughtId
    );
    event TokenSwapUnderlying(
        address indexed buyer,
        uint256 tokensSold,
        uint256 tokensBought,
        uint128 soldId,
        uint128 boughtId
    );
    event AddLiquidity(
        address indexed provider,
        uint256[] tokenAmounts,
        uint256[] fees,
        uint256 invariant,
        uint256 lpTokenSupply
    );
    event RemoveLiquidityOne(
        address indexed provider,
        uint256 lpTokenAmount,
        uint256 lpTokenSupply,
        uint256 boughtId,
        uint256 tokensBought
    );
    event RemoveLiquidityImbalance(
        address indexed provider,
        uint256[] tokenAmounts,
        uint256[] fees,
        uint256 invariant,
        uint256 lpTokenSupply
    );
    event NewAdminFee(uint256 newAdminFee);
    event NewSwapFee(uint256 newSwapFee);
    event NewWithdrawFee(uint256 newWithdrawFee);

    struct MetaSwap {
        // Meta-Swap related parameters
        ISwap baseSwap;
        uint256 baseVirtualPrice;
        uint256 baseCacheLastUpdated;
        IERC20[] baseTokens;
    }

    // Struct storing variables used in calculations in the
    // calculateWithdrawOneTokenDY function to avoid stack too deep errors
    struct CalculateWithdrawOneTokenDYInfo {
        uint256 d0;
        uint256 d1;
        uint256 newY;
        uint256 feePerToken;
        uint256 preciseA;
        uint256 xpi;
    }

    // Struct storing variables used in calculation in removeLiquidityImbalance function
    // to avoid stack too deep error
    struct ManageLiquidityInfo {
        uint256 d0;
        uint256 d1;
        uint256 d2;
        LPToken lpToken;
        uint256 totalSupply;
        uint256 preciseA;
        uint256 baseVirtualPrice;
        uint256[] tokenPrecisionMultipliers;
        uint256[] newBalances;
    }

    struct SwapUnderlyingInfo {
        uint256 x;
        uint256 dx;
        uint256 dy;
        uint8 metaIndexFrom;
        uint8 metaIndexTo;
        uint256[] oldBalances;
        IERC20[] baseTokens;
        IERC20 tokenFrom;
        IERC20 tokenTo;
        uint256 baseVirtualPrice;
    }

    struct CalculateSwapUnderlyingInfo {
        uint256 baseVirtualPrice;
        ISwap baseSwap;
        uint8 baseLPTokenIndex;
        uint8 baseTokensLength;
        uint8 metaIndexTo;
        uint256 x;
        uint256 dy;
    }

    // the precision all pools tokens will be converted to
    uint8 public constant POOL_PRECISION_DECIMALS = 18;

    // the denominator used to calculate admin and LP fees. For example, an
    // LP fee might be something like tradeAmount.mul(fee).div(FEE_DENOMINATOR)
    uint256 private constant FEE_DENOMINATOR = 10**10;

    // Constant value used as max loop limit
    uint256 private constant MAX_LOOP_LIMIT = 256;

    // Precision used in A parameter calculation
    uint256 public constant A_PRECISION = 100;

    // Cache expire time for the stored value of base swap's virtual price
    uint256 public constant BASE_CACHE_EXPIRE_TIME = 10 minutes;
    uint256 public constant BASE_VIRTUAL_PRICE_PRECISION = 10**18;

    /*** VIEW & PURE FUNCTIONS ***/

    /**
     * @notice Return A in its raw precision
     * @dev See the StableSwap paper for details
     * @param self Swap struct to read from
     * @return A parameter in its raw precision form
     */
    function getAPrecise(SwapUtils.Swap storage self)
        public
        view
        returns (uint256)
    {
        uint256 t1 = self.futureATime; // time when ramp is finished
        uint256 a1 = self.futureA; // final A value when ramp is finished

        if (block.timestamp < t1) {
            uint256 t0 = self.initialATime; // time when ramp is started
            uint256 a0 = self.initialA; // initial A value when ramp is started
            if (a1 > a0) {
                // a0 + (a1 - a0) * (block.timestamp - t0) / (t1 - t0)
                return
                    a0.add(
                        a1.sub(a0).mul(block.timestamp.sub(t0)).div(t1.sub(t0))
                    );
            } else {
                // a0 - (a0 - a1) * (block.timestamp - t0) / (t1 - t0)
                return
                    a0.sub(
                        a0.sub(a1).mul(block.timestamp.sub(t0)).div(t1.sub(t0))
                    );
            }
        } else {
            return a1;
        }
    }

    function _updateBaseVirtualPrice(MetaSwap storage metaSwapStorage)
        internal
        returns (uint256)
    {
        if (
            block.timestamp >
            metaSwapStorage.baseCacheLastUpdated + BASE_CACHE_EXPIRE_TIME
        ) {
            uint256 baseVirtualPrice =
                ISwap(metaSwapStorage.baseSwap).getVirtualPrice();
            metaSwapStorage.baseVirtualPrice = baseVirtualPrice;
            metaSwapStorage.baseCacheLastUpdated = block.timestamp;
            return baseVirtualPrice;
        } else {
            return metaSwapStorage.baseVirtualPrice;
        }
    }

    function _getBaseVirtualPrice(
        MetaSwap storage metaSwapStorage,
        ISwap baseSwap
    ) internal view returns (uint256) {
        if (
            block.timestamp >
            metaSwapStorage.baseCacheLastUpdated + BASE_CACHE_EXPIRE_TIME
        ) {
            return baseSwap.getVirtualPrice();
        } else {
            return metaSwapStorage.baseVirtualPrice;
        }
    }

    function _getBaseVirtualPrice(MetaSwap storage metaSwapStorage)
        internal
        view
        returns (uint256)
    {
        return _getBaseVirtualPrice(metaSwapStorage, metaSwapStorage.baseSwap);
    }

    /**
     * @notice Calculate the dy, the amount of selected token that user receives.
     * @param account the address that is withdrawing
     * @param tokenAmount the amount to withdraw in the pool's precision
     * @param tokenIndex which token will be withdrawn
     * @param self Swap struct to read from
     * @return dy the amount of token user will receive
     */
    function calculateWithdrawOneToken(
        SwapUtils.Swap storage self,
        MetaSwap storage metaSwapStorage,
        address account,
        uint256 tokenAmount,
        uint8 tokenIndex
    ) external view returns (uint256 dy) {
        (dy, ) = calculateWithdrawOneToken(
            self,
            account,
            tokenAmount,
            tokenIndex,
            _getBaseVirtualPrice(metaSwapStorage),
            self.lpToken.totalSupply()
        );
    }

    function calculateWithdrawOneToken(
        SwapUtils.Swap storage self,
        address account,
        uint256 tokenAmount,
        uint8 tokenIndex,
        uint256 baseVirtualPrice,
        uint256 totalSupply
    ) internal view returns (uint256, uint256) {
        uint256 dy;
        uint256 dySwapFee;

        {
            uint256 currentY;
            uint256 newY;

            (dy, newY, currentY) = calculateWithdrawOneTokenDY(
                self,
                tokenIndex,
                tokenAmount,
                baseVirtualPrice,
                totalSupply
            );

            dySwapFee = currentY
                .sub(newY)
                .div(self.tokenPrecisionMultipliers[tokenIndex])
                .sub(dy);
        }

        dy = dy
            .mul(
            FEE_DENOMINATOR.sub(calculateCurrentWithdrawFee(self, account))
        )
            .div(FEE_DENOMINATOR);

        return (dy, dySwapFee);
    }

    /**
     * @notice Calculate the dy of withdrawing in one token
     * @param self Swap struct to read from
     * @param tokenIndex which token will be withdrawn
     * @param tokenAmount the amount to withdraw in the pools precision
     * @return the d and the new y after withdrawing one token
     */
    function calculateWithdrawOneTokenDY(
        SwapUtils.Swap storage self,
        uint8 tokenIndex,
        uint256 tokenAmount,
        uint256 baseVirtualPrice,
        uint256 totalSupply
    )
        internal
        view
        returns (
            uint256,
            uint256,
            uint256
        )
    {
        // Get the current D, then solve the stableswap invariant
        // y_i for D - tokenAmount
        uint256[] memory xp = _xp(self, baseVirtualPrice);
        require(tokenIndex < xp.length, "Token index out of range");

        CalculateWithdrawOneTokenDYInfo memory v =
            CalculateWithdrawOneTokenDYInfo(0, 0, 0, 0, 0, 0);
        v.preciseA = getAPrecise(self);
        v.d0 = getD(xp, v.preciseA);
        v.d1 = v.d0.sub(tokenAmount.mul(v.d0).div(totalSupply));

        require(tokenAmount <= xp[tokenIndex], "Withdraw exceeds available");

        v.newY = getYD(v.preciseA, tokenIndex, xp, v.d1);

        uint256[] memory xpReduced = new uint256[](xp.length);

        v.feePerToken = _feePerToken(self);
        for (uint256 i = 0; i < xp.length; i++) {
            v.xpi = xp[i];
            // if i == tokenIndex, dxExpected = xp[i] * d1 / d0 - newY
            // else dxExpected = xp[i] - (xp[i] * d1 / d0)
            // xpReduced[i] -= dxExpected * fee / FEE_DENOMINATOR
            xpReduced[i] = v.xpi.sub(
                (
                    (i == tokenIndex)
                        ? v.xpi.mul(v.d1).div(v.d0).sub(v.newY)
                        : v.xpi.sub(v.xpi.mul(v.d1).div(v.d0))
                )
                    .mul(v.feePerToken)
                    .div(FEE_DENOMINATOR)
            );
        }

        uint256 dy =
            xpReduced[tokenIndex].sub(
                getYD(v.preciseA, tokenIndex, xpReduced, v.d1)
            );
        dy = dy.sub(1).div(self.tokenPrecisionMultipliers[tokenIndex]);

        if (tokenIndex == xp.length - 1) {
            dy = dy.mul(BASE_VIRTUAL_PRICE_PRECISION).div(baseVirtualPrice);
        }

        return (dy, v.newY, xp[tokenIndex]);
    }

    /**
     * @notice Calculate the price of a token in the pool with given
     * precision-adjusted balances and a particular D.
     *
     * @dev This is accomplished via solving the invariant iteratively.
     * See the StableSwap paper and Curve.fi implementation for further details.
     *
     * x_1**2 + x1 * (sum' - (A*n**n - 1) * D / (A * n**n)) = D ** (n + 1) / (n ** (2 * n) * prod' * A)
     * x_1**2 + b*x_1 = c
     * x_1 = (x_1**2 + c) / (2*x_1 + b)
     *
     * @param a the amplification coefficient * n * (n - 1). See the StableSwap paper for details.
     * @param tokenIndex Index of token we are calculating for.
     * @param xp a precision-adjusted set of pool balances. Array should be
     * the same cardinality as the pool.
     * @param d the stableswap invariant
     * @return the price of the token, in the same precision as in xp
     */
    function getYD(
        uint256 a,
        uint8 tokenIndex,
        uint256[] memory xp,
        uint256 d
    ) internal pure returns (uint256) {
        uint256 numTokens = xp.length;
        require(tokenIndex < numTokens, "Token not found");

        uint256 c = d;
        uint256 s;
        uint256 nA = a.mul(numTokens);

        for (uint256 i = 0; i < numTokens; i++) {
            if (i != tokenIndex) {
                s = s.add(xp[i]);
                c = c.mul(d).div(xp[i].mul(numTokens));
                // If we were to protect the division loss we would have to keep the denominator separate
                // and divide at the end. However this leads to overflow with large numTokens or/and D.
                // c = c * D * D * D * ... overflow!
            }
        }
        c = c.mul(d).mul(A_PRECISION).div(nA.mul(numTokens));

        uint256 b = s.add(d.mul(A_PRECISION).div(nA));
        uint256 yPrev;
        uint256 y = d;
        for (uint256 i = 0; i < MAX_LOOP_LIMIT; i++) {
            yPrev = y;
            y = y.mul(y).add(c).div(y.mul(2).add(b).sub(d));
            if (y.within1(yPrev)) {
                return y;
            }
        }
        revert("Approximation did not converge");
    }

    /**
     * @notice Get D, the StableSwap invariant, based on a set of balances and a particular A.
     * @param xp a precision-adjusted set of pool balances. Array should be the same cardinality
     * as the pool.
     * @param a the amplification coefficient * n * (n - 1) in A_PRECISION.
     * See the StableSwap paper for details
     * @return the invariant, at the precision of the pool
     */
    function getD(uint256[] memory xp, uint256 a)
        internal
        pure
        returns (uint256)
    {
        uint256 numTokens = xp.length;
        uint256 s;
        for (uint256 i = 0; i < numTokens; i++) {
            s = s.add(xp[i]);
        }
        if (s == 0) {
            return 0;
        }

        uint256 prevD;
        uint256 d = s;
        uint256 nA = a.mul(numTokens);

        for (uint256 i = 0; i < MAX_LOOP_LIMIT; i++) {
            uint256 dP = d;
            for (uint256 j = 0; j < numTokens; j++) {
                dP = dP.mul(d).div(xp[j].mul(numTokens));
                // If we were to protect the division loss we would have to keep the denominator separate
                // and divide at the end. However this leads to overflow with large numTokens or/and D.
                // dP = dP * D * D * D * ... overflow!
            }
            prevD = d;
            d = nA.mul(s).div(A_PRECISION).add(dP.mul(numTokens)).mul(d).div(
                nA.sub(A_PRECISION).mul(d).div(A_PRECISION).add(
                    numTokens.add(1).mul(dP)
                )
            );
            if (d.within1(prevD)) {
                return d;
            }
        }

        // Convergence should occur in 4 loops or less. If this is reached, there may be something wrong
        // with the pool. If this were to occur repeatedly, LPs should withdraw via `removeLiquidity()`
        // function which does not rely on D.
        revert("D does not converge");
    }

    /**
     * @notice Given a set of balances and precision multipliers, return the
     * precision-adjusted balances.
     *
     * @param balances an array of token balances, in their native precisions.
     * These should generally correspond with pooled tokens.
     *
     * @param precisionMultipliers an array of multipliers, corresponding to
     * the amounts in the balances array. When multiplied together they
     * should yield amounts at the pool's precision.
     *
     * @return an array of amounts "scaled" to the pool's precision
     */
    function _xp(
        uint256[] memory balances,
        uint256[] memory precisionMultipliers,
        uint256 baseVirtualPrice
    ) internal pure returns (uint256[] memory) {
        uint256 numTokens = balances.length;
        require(
            numTokens == precisionMultipliers.length,
            "Balances must match multipliers"
        );
        uint256[] memory xp = new uint256[](numTokens);
        for (uint256 i = 0; i < numTokens; i++) {
            xp[i] = balances[i].mul(precisionMultipliers[i]);
        }
        uint256 baseLPTokenIndex = numTokens - 1;
        xp[baseLPTokenIndex] = xp[baseLPTokenIndex].mul(baseVirtualPrice).div(
            BASE_VIRTUAL_PRICE_PRECISION
        );
        return xp;
    }

    /**
     * @notice Return the precision-adjusted balances of all tokens in the pool
     * @param self Swap struct to read from
     * @param balances array of balances to scale
     * @return balances array "scaled" to the pool's precision, allowing
     * them to be more easily compared.
     */
    function _xp(
        SwapUtils.Swap storage self,
        uint256[] memory balances,
        uint256 baseVirtualPrice
    ) internal view returns (uint256[] memory) {
        return _xp(balances, self.tokenPrecisionMultipliers, baseVirtualPrice);
    }

    /**
     * @notice Return the precision-adjusted balances of all tokens in the pool
     * @param self Swap struct to read from
     * @return the pool balances "scaled" to the pool's precision, allowing
     * them to be more easily compared.
     */
    function _xp(SwapUtils.Swap storage self, uint256 baseVirtualPrice)
        internal
        view
        returns (uint256[] memory)
    {
        return
            _xp(
                self.balances,
                self.tokenPrecisionMultipliers,
                baseVirtualPrice
            );
    }

    /**
     * @notice Get the virtual price, to help calculate profit
     * @param self Swap struct to read from
     * @return the virtual price, scaled to precision of POOL_PRECISION_DECIMALS
     */
    function getVirtualPrice(
        SwapUtils.Swap storage self,
        MetaSwap storage metaSwapStorage
    ) external view returns (uint256) {
        uint256 d =
            getD(
                _xp(self, _getBaseVirtualPrice(metaSwapStorage)),
                getAPrecise(self)
            );
        ERC20 lpToken = self.lpToken;
        uint256 supply = lpToken.totalSupply();
        if (supply != 0) {
            return d.mul(10**uint256(lpToken.decimals())).div(supply);
        }
        return 0;
    }

    /**
     * @notice Calculate the new balances of the tokens given the indexes of the token
     * that is swapped from (FROM) and the token that is swapped to (TO).
     * This function is used as a helper function to calculate how much TO token
     * the user should receive on swap.
     *
     * @param preciseA value of A parameter to use for calculation
     * @param tokenIndexFrom index of FROM token
     * @param tokenIndexTo index of TO token
     * @param x the new total amount of FROM token
     * @param xp balances of the tokens in the pool
     * @return the amount of TO token that should remain in the pool
     */
    function getY(
        uint256 preciseA,
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 x,
        uint256[] memory xp
    ) internal pure returns (uint256) {
        uint256 numTokens = xp.length;
        require(
            tokenIndexFrom != tokenIndexTo,
            "Can't compare token to itself"
        );
        require(
            tokenIndexFrom < numTokens && tokenIndexTo < numTokens,
            "Tokens must be in pool"
        );

        uint256 d = getD(xp, preciseA);
        uint256 c = d;
        uint256 s;
        uint256 nA = numTokens.mul(preciseA);

        uint256 _x;
        for (uint256 i = 0; i < numTokens; i++) {
            if (i == tokenIndexFrom) {
                _x = x;
            } else if (i != tokenIndexTo) {
                _x = xp[i];
            } else {
                continue;
            }
            s = s.add(_x);
            c = c.mul(d).div(_x.mul(numTokens));
            // If we were to protect the division loss we would have to keep the denominator separate
            // and divide at the end. However this leads to overflow with large numTokens or/and D.
            // c = c * D * D * D * ... overflow!
        }
        c = c.mul(d).mul(A_PRECISION).div(nA.mul(numTokens));
        uint256 b = s.add(d.mul(A_PRECISION).div(nA));
        uint256 yPrev;
        uint256 y = d;

        // iterative approximation
        for (uint256 i = 0; i < MAX_LOOP_LIMIT; i++) {
            yPrev = y;
            y = y.mul(y).add(c).div(y.mul(2).add(b).sub(d));
            if (y.within1(yPrev)) {
                return y;
            }
        }
        revert("Approximation did not converge");
    }

    /**
     * @notice Externally calculates a swap between two tokens.
     * @param self Swap struct to read from
     * @param tokenIndexFrom the token to sell
     * @param tokenIndexTo the token to buy
     * @param dx the number of tokens to sell. If the token charges a fee on transfers,
     * use the amount that gets transferred after the fee.
     * @return dy the number of tokens the user will get
     */
    function calculateSwap(
        SwapUtils.Swap storage self,
        MetaSwap storage metaSwapStorage,
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx
    ) external view returns (uint256 dy) {
        (dy, ) = _calculateSwap(
            self,
            tokenIndexFrom,
            tokenIndexTo,
            dx,
            _getBaseVirtualPrice(metaSwapStorage)
        );
    }

    /**
     * @notice Internally calculates a swap between two tokens.
     *
     * @dev The caller is expected to transfer the actual amounts (dx and dy)
     * using the token contracts.
     *
     * @param self Swap struct to read from
     * @param tokenIndexFrom the token to sell
     * @param tokenIndexTo the token to buy
     * @param dx the number of tokens to sell. If the token charges a fee on transfers,
     * use the amount that gets transferred after the fee.
     * @return dy the number of tokens the user will get
     * @return dyFee the associated fee
     */
    function _calculateSwap(
        SwapUtils.Swap storage self,
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx,
        uint256 baseVirtualPrice
    ) internal view returns (uint256 dy, uint256 dyFee) {
        uint256[] memory xp = _xp(self, baseVirtualPrice);
        require(
            tokenIndexFrom < xp.length && tokenIndexTo < xp.length,
            "Token index out of range"
        );
        uint256 x =
            dx.mul(self.tokenPrecisionMultipliers[tokenIndexFrom]).add(
                xp[tokenIndexFrom]
            );
        uint256 y =
            getY(getAPrecise(self), tokenIndexFrom, tokenIndexTo, x, xp);
        dy = xp[tokenIndexTo].sub(y).sub(1);
        dyFee = dy.mul(self.swapFee).div(FEE_DENOMINATOR);
        dy = dy.sub(dyFee).div(self.tokenPrecisionMultipliers[tokenIndexTo]);
    }

    function calculateSwapUnderlying(
        SwapUtils.Swap storage self,
        MetaSwap storage metaSwapStorage,
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx
    ) external view returns (uint256) {
        CalculateSwapUnderlyingInfo memory v =
            CalculateSwapUnderlyingInfo(
                _getBaseVirtualPrice(metaSwapStorage),
                metaSwapStorage.baseSwap,
                0,
                uint8(metaSwapStorage.baseTokens.length),
                0,
                0,
                0
            );

        uint256[] memory xp = _xp(self, v.baseVirtualPrice);
        v.baseLPTokenIndex = uint8(xp.length) - 1;
        {
            uint8 maxRange = v.baseLPTokenIndex + v.baseTokensLength;
            require(
                tokenIndexFrom < maxRange && tokenIndexTo < maxRange,
                "Token index out of range"
            );
        }

        if (tokenIndexFrom < v.baseLPTokenIndex) {
            // tokenFrom is from this pool
            v.x = xp[tokenIndexFrom].add(
                dx.mul(self.tokenPrecisionMultipliers[tokenIndexFrom])
            );
        } else {
            // tokenFrom is from the base pool
            tokenIndexFrom = tokenIndexFrom - v.baseLPTokenIndex;
            if (tokenIndexTo < v.baseLPTokenIndex) {
                uint256[] memory baseInputs = new uint256[](v.baseTokensLength);
                baseInputs[tokenIndexFrom] = dx;
                v.x = v
                    .baseSwap
                    .calculateTokenAmount(address(this), baseInputs, true)
                    .mul(v.baseVirtualPrice)
                    .div(BASE_VIRTUAL_PRICE_PRECISION)
                    .add(xp[v.baseLPTokenIndex]);
            } else {
                // both from and to are from the base pool
                return
                    v.baseSwap.calculateSwap(
                        tokenIndexFrom,
                        tokenIndexTo - v.baseLPTokenIndex,
                        dx
                    );
            }
            tokenIndexFrom = v.baseLPTokenIndex;
        }

        v.metaIndexTo = v.baseLPTokenIndex;
        if (tokenIndexTo < v.baseLPTokenIndex) {
            v.metaIndexTo = tokenIndexTo;
        }

        {
            uint256 y =
                getY(getAPrecise(self), tokenIndexFrom, v.metaIndexTo, v.x, xp);
            v.dy = xp[v.metaIndexTo].sub(y).sub(1);
            uint256 dyFee = v.dy.mul(self.swapFee).div(FEE_DENOMINATOR);
            v.dy = v.dy.sub(dyFee);
        }

        if (tokenIndexTo < v.baseLPTokenIndex) {
            // tokenTo is from this pool
            v.dy = v.dy.div(self.tokenPrecisionMultipliers[v.metaIndexTo]);
        } else {
            // tokenTo is from the base pool
            v.dy = v.baseSwap.calculateRemoveLiquidityOneToken(
                address(this),
                v.dy.mul(BASE_VIRTUAL_PRICE_PRECISION).div(v.baseVirtualPrice),
                tokenIndexTo - v.baseLPTokenIndex
            );
        }

        return v.dy;
    }

    /**
     * @notice Calculate the fee that is applied when the given user withdraws.
     * Withdraw fee decays linearly over 4 weeks.
     * @param user address you want to calculate withdraw fee of
     * @return current withdraw fee of the user
     */
    function calculateCurrentWithdrawFee(
        SwapUtils.Swap storage self,
        address user
    ) public view returns (uint256) {
        uint256 endTime = self.depositTimestamp[user].add(4 weeks);
        if (endTime > block.timestamp) {
            uint256 timeLeftover = endTime.sub(block.timestamp);
            return
                self
                    .defaultWithdrawFee
                    .mul(self.withdrawFeeMultiplier[user])
                    .mul(timeLeftover)
                    .div(4 weeks)
                    .div(FEE_DENOMINATOR);
        }
        return 0;
    }

    /**
     * @notice A simple method to calculate prices from deposits or
     * withdrawals, excluding fees but including slippage. This is
     * helpful as an input into the various "min" parameters on calls
     * to fight front-running
     *
     * @dev This shouldn't be used outside frontends for user estimates.
     *
     * @param self Swap struct to read from
     * @param account address of the account depositing or withdrawing tokens
     * @param amounts an array of token amounts to deposit or withdrawal,
     * corresponding to pooledTokens. The amount should be in each
     * pooled token's native precision. If a token charges a fee on transfers,
     * use the amount that gets transferred after the fee.
     * @param deposit whether this is a deposit or a withdrawal
     * @return if deposit was true, total amount of lp token that will be minted and if
     * deposit was false, total amount of lp token that will be burned
     */
    function calculateTokenAmount(
        SwapUtils.Swap storage self,
        MetaSwap storage metaSwapStorage,
        address account,
        uint256[] calldata amounts,
        bool deposit
    ) external view returns (uint256) {
        uint256 a = getAPrecise(self);
        uint256 d0;
        uint256 d1;
        {
            uint256 baseVirtualPrice = _getBaseVirtualPrice(metaSwapStorage);
            uint256[] memory balances1 = self.balances;
            uint256 numTokens = balances1.length;
            d0 = getD(_xp(self, balances1, baseVirtualPrice), a);
            for (uint256 i = 0; i < numTokens; i++) {
                if (deposit) {
                    balances1[i] = balances1[i].add(amounts[i]);
                } else {
                    balances1[i] = balances1[i].sub(
                        amounts[i],
                        "Cannot withdraw more than available"
                    );
                }
            }
            d1 = getD(_xp(self, balances1, baseVirtualPrice), a);
        }
        uint256 totalSupply = self.lpToken.totalSupply();

        if (deposit) {
            return d1.sub(d0).mul(totalSupply).div(d0);
        } else {
            return
                d0.sub(d1).mul(totalSupply).div(d0).mul(FEE_DENOMINATOR).div(
                    FEE_DENOMINATOR.sub(
                        calculateCurrentWithdrawFee(self, account)
                    )
                );
        }
    }

    /**
     * @notice internal helper function to calculate fee per token multiplier used in
     * swap fee calculations
     * @param self Swap struct to read from
     */
    function _feePerToken(SwapUtils.Swap storage self)
        internal
        view
        returns (uint256)
    {
        IERC20[] memory pooledTokens = self.pooledTokens;
        return
            self.swapFee.mul(pooledTokens.length).div(
                pooledTokens.length.sub(1).mul(4)
            );
    }

    /*** STATE MODIFYING FUNCTIONS ***/

    /**
     * @notice swap two tokens in the pool
     * @param self Swap struct to read from and write to
     * @param tokenIndexFrom the token the user wants to sell
     * @param tokenIndexTo the token the user wants to buy
     * @param dx the amount of tokens the user wants to sell
     * @param minDy the min amount the user would like to receive, or revert.
     * @return amount of token user received on swap
     */
    function swap(
        SwapUtils.Swap storage self,
        MetaSwap storage metaSwapStorage,
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx,
        uint256 minDy
    ) external returns (uint256) {
        uint256 transferredDx;
        {
            IERC20 tokenFrom = self.pooledTokens[tokenIndexFrom];
            require(
                dx <= tokenFrom.balanceOf(msg.sender),
                "Cannot swap more than you own"
            );

            {
                // Transfer tokens first to see if a fee was charged on transfer
                uint256 beforeBalance = tokenFrom.balanceOf(address(this));
                tokenFrom.safeTransferFrom(msg.sender, address(this), dx);

                // Use the actual transferred amount for AMM math
                transferredDx = tokenFrom.balanceOf(address(this)).sub(
                    beforeBalance
                );
            }
        }

        (uint256 dy, uint256 dyFee) =
            _calculateSwap(
                self,
                tokenIndexFrom,
                tokenIndexTo,
                transferredDx,
                _updateBaseVirtualPrice(metaSwapStorage)
            );
        require(dy >= minDy, "Swap didn't result in min tokens");

        uint256 dyAdminFee =
            dyFee.mul(self.adminFee).div(FEE_DENOMINATOR).div(
                self.tokenPrecisionMultipliers[tokenIndexTo]
            );

        self.balances[tokenIndexFrom] = self.balances[tokenIndexFrom].add(
            transferredDx
        );
        self.balances[tokenIndexTo] = self.balances[tokenIndexTo].sub(dy).sub(
            dyAdminFee
        );

        self.pooledTokens[tokenIndexTo].safeTransfer(msg.sender, dy);

        emit TokenSwap(
            msg.sender,
            transferredDx,
            dy,
            tokenIndexFrom,
            tokenIndexTo
        );

        return dy;
    }

    function swapUnderlying(
        SwapUtils.Swap storage self,
        MetaSwap storage metaSwapStorage,
        uint8 tokenIndexFrom,
        uint8 tokenIndexTo,
        uint256 dx,
        uint256 minDy
    ) external returns (uint256) {
        SwapUnderlyingInfo memory v =
            SwapUnderlyingInfo(
                0,
                0,
                0,
                0,
                0,
                self.balances,
                metaSwapStorage.baseTokens,
                IERC20(address(0)),
                IERC20(address(0)),
                _updateBaseVirtualPrice(metaSwapStorage)
            );

        uint8 baseLPTokenIndex = uint8(v.oldBalances.length) - 1;

        {
            uint8 maxRange = baseLPTokenIndex + uint8(v.baseTokens.length);
            require(
                tokenIndexFrom < maxRange && tokenIndexTo < maxRange,
                "Token index out of range"
            );
        }

        ISwap baseSwap = metaSwapStorage.baseSwap;

        // Find the address of the token swapping from
        if (tokenIndexFrom < baseLPTokenIndex) {
            v.tokenFrom = self.pooledTokens[tokenIndexFrom];
            v.metaIndexFrom = tokenIndexFrom;
        } else {
            v.tokenFrom = v.baseTokens[tokenIndexFrom - baseLPTokenIndex];
            v.metaIndexFrom = baseLPTokenIndex;
        }

        // Find the address of the token swapping to
        if (tokenIndexTo < baseLPTokenIndex) {
            v.tokenTo = self.pooledTokens[tokenIndexTo];
            v.metaIndexTo = tokenIndexTo;
        } else {
            v.tokenTo = v.baseTokens[tokenIndexTo - baseLPTokenIndex];
            v.metaIndexTo = baseLPTokenIndex;
        }

        v.dx = v.tokenFrom.balanceOf(address(this));
        v.tokenFrom.safeTransferFrom(msg.sender, address(this), dx);
        v.dx = v.tokenFrom.balanceOf(address(this)).sub(v.dx); // update dx in case of fee on transfer

        if (
            tokenIndexFrom < baseLPTokenIndex || tokenIndexTo < baseLPTokenIndex
        ) {
            uint256[] memory xp = _xp(self, v.oldBalances, v.baseVirtualPrice);

            if (tokenIndexFrom < baseLPTokenIndex) {
                v.x =
                    xp[tokenIndexFrom] +
                    dx.mul(self.tokenPrecisionMultipliers[tokenIndexFrom]);
            } else {
                // tokenFrom is in the base pool
                uint256[] memory baseAmounts =
                    new uint256[](v.baseTokens.length);
                baseAmounts[tokenIndexFrom - baseLPTokenIndex] = v.dx;
                IERC20 baseLPToken = self.pooledTokens[baseLPTokenIndex];
                v.x = baseLPToken.balanceOf(address(this));
                // Add liquidity to the underlying swap contract
                baseSwap.addLiquidity(baseAmounts, 0, block.timestamp);
                // Now we have more of the base LP token
                v.dx = baseLPToken.balanceOf(address(this)).sub(v.x);
                v.x = v
                    .dx
                    .mul(v.baseVirtualPrice)
                    .div(BASE_VIRTUAL_PRICE_PRECISION)
                    .add(xp[baseLPTokenIndex]);
            }

            uint256 dyFee;
            {
                uint256 y =
                    getY(
                        getAPrecise(self),
                        v.metaIndexFrom,
                        v.metaIndexTo,
                        v.x,
                        xp
                    );
                v.dy = xp[v.metaIndexTo].sub(y).sub(1);
                dyFee = v.dy.mul(self.swapFee).div(FEE_DENOMINATOR);
                v.dy = v.dy.sub(dyFee).div(
                    self.tokenPrecisionMultipliers[v.metaIndexTo]
                );
            }

            if (tokenIndexTo >= baseLPTokenIndex) {
                v.dy = v.dy.mul(BASE_VIRTUAL_PRICE_PRECISION).div(
                    v.baseVirtualPrice
                );
            }

            {
                uint256 dyAdminFee =
                    dyFee.mul(self.adminFee).div(FEE_DENOMINATOR);
                dyAdminFee = dyAdminFee.div(
                    self.tokenPrecisionMultipliers[v.metaIndexTo]
                );
                self.balances[v.metaIndexFrom] = v.oldBalances[v.metaIndexFrom]
                    .add(v.dx);
                self.balances[v.metaIndexTo] = v.oldBalances[v.metaIndexTo]
                    .sub(v.dy)
                    .sub(dyAdminFee);
            }

            if (tokenIndexTo >= baseLPTokenIndex) {
                // tokenTo is from the base pool
                // burn the LP token and withdraw the desired token from the base pool
                uint256 oldBalance = v.tokenTo.balanceOf(address(this));
                baseSwap.removeLiquidityOneToken(
                    v.dy,
                    tokenIndexTo - baseLPTokenIndex,
                    0,
                    block.timestamp
                );
                v.dy = v.tokenTo.balanceOf(address(this)) - oldBalance;
            }
            require(v.dy >= minDy, "Swap didn't result in min tokens");
        } else {
            // Both tokens are from the base swap pool
            v.dy = v.tokenTo.balanceOf(address(this));
            baseSwap.swap(
                tokenIndexFrom - baseLPTokenIndex,
                tokenIndexTo - baseLPTokenIndex,
                v.dx,
                minDy,
                block.timestamp
            );
            v.dy = v.tokenTo.balanceOf(address(this)).sub(v.dy);
        }

        v.tokenTo.safeTransfer(msg.sender, v.dy);

        emit TokenSwapUnderlying(
            msg.sender,
            dx,
            v.dy,
            tokenIndexFrom,
            tokenIndexTo
        );

        return v.dy;
    }

    /**
     * @notice Add liquidity to the pool
     * @param self Swap struct to read from and write to
     * @param amounts the amounts of each token to add, in their native precision
     * @param minToMint the minimum LP tokens adding this amount of liquidity
     * should mint, otherwise revert. Handy for front-running mitigation
     * allowed addresses. If the pool is not in the guarded launch phase, this parameter will be ignored.
     * @return amount of LP token user received
     */
    function addLiquidity(
        SwapUtils.Swap storage self,
        MetaSwap storage metaSwapStorage,
        uint256[] memory amounts,
        uint256 minToMint
    ) external returns (uint256) {
        IERC20[] memory pooledTokens = self.pooledTokens;
        require(
            amounts.length == self.pooledTokens.length,
            "Amounts must match pooled tokens"
        );

        uint256[] memory fees = new uint256[](pooledTokens.length);

        // current state
        ManageLiquidityInfo memory v =
            ManageLiquidityInfo(
                0,
                0,
                0,
                self.lpToken,
                0,
                getAPrecise(self),
                _updateBaseVirtualPrice(metaSwapStorage),
                self.tokenPrecisionMultipliers,
                self.balances
            );
        v.totalSupply = v.lpToken.totalSupply();

        if (v.totalSupply != 0) {
            v.d0 = getD(
                _xp(
                    v.newBalances,
                    v.tokenPrecisionMultipliers,
                    v.baseVirtualPrice
                ),
                v.preciseA
            );
        }

        for (uint256 i = 0; i < pooledTokens.length; i++) {
            require(
                v.totalSupply != 0 || amounts[i] > 0,
                "Must supply all tokens in pool"
            );

            // Transfer tokens first to see if a fee was charged on transfer
            if (amounts[i] != 0) {
                uint256 beforeBalance =
                    pooledTokens[i].balanceOf(address(this));
                pooledTokens[i].safeTransferFrom(
                    msg.sender,
                    address(this),
                    amounts[i]
                );

                // Update the amounts[] with actual transfer amount
                amounts[i] = pooledTokens[i].balanceOf(address(this)).sub(
                    beforeBalance
                );
            }

            v.newBalances[i] = v.newBalances[i].add(amounts[i]);
        }

        // invariant after change
        v.d1 = getD(
            _xp(v.newBalances, v.tokenPrecisionMultipliers, v.baseVirtualPrice),
            v.preciseA
        );
        require(v.d1 > v.d0, "D should increase");

        // updated to reflect fees and calculate the user's LP tokens
        v.d2 = v.d1;
        uint256 toMint;

        if (v.totalSupply != 0) {
            uint256 feePerToken = _feePerToken(self);
            for (uint256 i = 0; i < pooledTokens.length; i++) {
                uint256 idealBalance = v.d1.mul(self.balances[i]).div(v.d0);
                fees[i] = feePerToken
                    .mul(idealBalance.difference(v.newBalances[i]))
                    .div(FEE_DENOMINATOR);
                self.balances[i] = v.newBalances[i].sub(
                    fees[i].mul(self.adminFee).div(FEE_DENOMINATOR)
                );
                v.newBalances[i] = v.newBalances[i].sub(fees[i]);
            }
            v.d2 = getD(
                _xp(
                    v.newBalances,
                    v.tokenPrecisionMultipliers,
                    v.baseVirtualPrice
                ),
                v.preciseA
            );
            toMint = v.d2.sub(v.d0).mul(v.totalSupply).div(v.d0);
        } else {
            // the initial depositor doesn't pay fees
            self.balances = v.newBalances;
            toMint = v.d1;
        }

        require(toMint >= minToMint, "Couldn't mint min requested");

        // mint the user's LP tokens
        self.lpToken.mint(msg.sender, toMint);

        emit AddLiquidity(
            msg.sender,
            amounts,
            fees,
            v.d1,
            v.totalSupply.add(toMint)
        );

        return toMint;
    }

    /**
     * @notice Remove liquidity from the pool all in one token.
     * @param self Swap struct to read from and write to
     * @param tokenAmount the amount of the lp tokens to burn
     * @param tokenIndex the index of the token you want to receive
     * @param minAmount the minimum amount to withdraw, otherwise revert
     * @return amount chosen token that user received
     */
    function removeLiquidityOneToken(
        SwapUtils.Swap storage self,
        MetaSwap storage metaSwapStorage,
        uint256 tokenAmount,
        uint8 tokenIndex,
        uint256 minAmount
    ) external returns (uint256) {
        LPToken lpToken = self.lpToken;
        uint256 totalSupply = lpToken.totalSupply();
        uint256 numTokens = self.pooledTokens.length;
        require(tokenAmount <= lpToken.balanceOf(msg.sender), ">LP.balanceOf");
        require(tokenIndex < numTokens, "Token not found");

        uint256 dyFee;
        uint256 dy;

        (dy, dyFee) = calculateWithdrawOneToken(
            self,
            msg.sender,
            tokenAmount,
            tokenIndex,
            _updateBaseVirtualPrice(metaSwapStorage),
            totalSupply
        );

        require(dy >= minAmount, "dy < minAmount");

        self.balances[tokenIndex] = self.balances[tokenIndex].sub(
            dy.add(dyFee.mul(self.adminFee).div(FEE_DENOMINATOR))
        );
        lpToken.burnFrom(msg.sender, tokenAmount);
        self.pooledTokens[tokenIndex].safeTransfer(msg.sender, dy);

        emit RemoveLiquidityOne(
            msg.sender,
            tokenAmount,
            totalSupply,
            tokenIndex,
            dy
        );

        return dy;
    }

    /**
     * @notice Remove liquidity from the pool, weighted differently than the
     * pool's current balances.
     *
     * @param self Swap struct to read from and write to
     * @param amounts how much of each token to withdraw
     * @param maxBurnAmount the max LP token provider is willing to pay to
     * remove liquidity. Useful as a front-running mitigation.
     * @return actual amount of LP tokens burned in the withdrawal
     */
    function removeLiquidityImbalance(
        SwapUtils.Swap storage self,
        MetaSwap storage metaSwapStorage,
        uint256[] memory amounts,
        uint256 maxBurnAmount
    ) public returns (uint256) {
        ManageLiquidityInfo memory v =
            ManageLiquidityInfo(
                0,
                0,
                0,
                self.lpToken,
                0,
                getAPrecise(self),
                _updateBaseVirtualPrice(metaSwapStorage),
                self.tokenPrecisionMultipliers,
                self.balances
            );
        v.totalSupply = v.lpToken.totalSupply();

        require(
            amounts.length == v.newBalances.length,
            "Amounts should match pool tokens"
        );
        require(
            maxBurnAmount <= v.lpToken.balanceOf(msg.sender) &&
                maxBurnAmount != 0,
            ">LP.balanceOf"
        );

        uint256 feePerToken = _feePerToken(self);

        uint256[] memory fees = new uint256[](v.newBalances.length);
        {
            uint256[] memory balances1 = new uint256[](v.newBalances.length);

            v.d0 = getD(
                _xp(
                    v.newBalances,
                    v.tokenPrecisionMultipliers,
                    v.baseVirtualPrice
                ),
                v.preciseA
            );
            for (uint256 i = 0; i < v.newBalances.length; i++) {
                balances1[i] = v.newBalances[i].sub(
                    amounts[i],
                    "Cannot withdraw more than available"
                );
            }
            v.d1 = getD(
                _xp(balances1, v.tokenPrecisionMultipliers, v.baseVirtualPrice),
                v.preciseA
            );

            for (uint256 i = 0; i < v.newBalances.length; i++) {
                uint256 idealBalance = v.d1.mul(v.newBalances[i]).div(v.d0);
                uint256 difference = idealBalance.difference(balances1[i]);
                fees[i] = feePerToken.mul(difference).div(FEE_DENOMINATOR);
                self.balances[i] = balances1[i].sub(
                    fees[i].mul(self.adminFee).div(FEE_DENOMINATOR)
                );
                balances1[i] = balances1[i].sub(fees[i]);
            }

            v.d2 = getD(
                _xp(balances1, v.tokenPrecisionMultipliers, v.baseVirtualPrice),
                v.preciseA
            );
        }

        uint256 tokenAmount = v.d0.sub(v.d2).mul(v.totalSupply).div(v.d0);
        require(tokenAmount != 0, "Burnt amount cannot be zero");
        tokenAmount = tokenAmount.add(1).mul(FEE_DENOMINATOR).div(
            FEE_DENOMINATOR.sub(calculateCurrentWithdrawFee(self, msg.sender))
        );

        require(tokenAmount <= maxBurnAmount, "tokenAmount > maxBurnAmount");

        v.lpToken.burnFrom(msg.sender, tokenAmount);

        for (uint256 i = 0; i < v.newBalances.length; i++) {
            self.pooledTokens[i].safeTransfer(msg.sender, amounts[i]);
        }

        emit RemoveLiquidityImbalance(
            msg.sender,
            amounts,
            fees,
            v.d1,
            v.totalSupply.sub(tokenAmount)
        );

        return tokenAmount;
    }
}

Settings
{
  "evmVersion": "istanbul",
  "libraries": {
    "contracts/meta/MetaSwap.sol:MetaSwap": {
      "SwapUtils": "0x02338Ee742ddCDe44488640F4edf1Aa947E670E7",
      "MetaSwapUtils": "0x91d1DBE983fBCbBAC198D5310f1d0C249bb54E65",
      "AmplificationUtils": "0x4604AF0eB93ADaA96a21D66636902e7353a25c02"
    }
  },
  "metadata": {
    "bytecodeHash": "ipfs",
    "useLiteralContent": true
  },
  "optimizer": {
    "enabled": true,
    "runs": 10000
  },
  "remappings": [],
  "outputSelection": {
    "*": {
      "*": [
        "evm.bytecode",
        "evm.deployedBytecode",
        "abi"
      ]
    }
  }
}

Contract ABI

[{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"provider","type":"address"},{"indexed":false,"internalType":"uint256[]","name":"tokenAmounts","type":"uint256[]"},{"indexed":false,"internalType":"uint256[]","name":"fees","type":"uint256[]"},{"indexed":false,"internalType":"uint256","name":"invariant","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"lpTokenSupply","type":"uint256"}],"name":"AddLiquidity","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"uint256","name":"newAdminFee","type":"uint256"}],"name":"NewAdminFee","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"uint256","name":"newDepositFee","type":"uint256"}],"name":"NewDepositFee","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"uint256","name":"newSwapFee","type":"uint256"}],"name":"NewSwapFee","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"uint256","name":"newWithdrawFee","type":"uint256"}],"name":"NewWithdrawFee","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"previousOwner","type":"address"},{"indexed":true,"internalType":"address","name":"newOwner","type":"address"}],"name":"OwnershipTransferred","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"address","name":"account","type":"address"}],"name":"Paused","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"uint256","name":"oldA","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"newA","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"initialTime","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"futureTime","type":"uint256"}],"name":"RampA","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"provider","type":"address"},{"indexed":false,"internalType":"uint256[]","name":"tokenAmounts","type":"uint256[]"},{"indexed":false,"internalType":"uint256","name":"lpTokenSupply","type":"uint256"}],"name":"RemoveLiquidity","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"provider","type":"address"},{"indexed":false,"internalType":"uint256[]","name":"tokenAmounts","type":"uint256[]"},{"indexed":false,"internalType":"uint256[]","name":"fees","type":"uint256[]"},{"indexed":false,"internalType":"uint256","name":"invariant","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"lpTokenSupply","type":"uint256"}],"name":"RemoveLiquidityImbalance","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"provider","type":"address"},{"indexed":false,"internalType":"uint256","name":"lpTokenAmount","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"lpTokenSupply","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"boughtId","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"tokensBought","type":"uint256"}],"name":"RemoveLiquidityOne","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"uint256","name":"currentA","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"time","type":"uint256"}],"name":"StopRampA","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"buyer","type":"address"},{"indexed":false,"internalType":"uint256","name":"tokensSold","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"tokensBought","type":"uint256"},{"indexed":false,"internalType":"uint128","name":"soldId","type":"uint128"},{"indexed":false,"internalType":"uint128","name":"boughtId","type":"uint128"}],"name":"TokenSwap","type":"event"},{"anonymous":false,"inputs":[{"indexed":true,"internalType":"address","name":"buyer","type":"address"},{"indexed":false,"internalType":"uint256","name":"tokensSold","type":"uint256"},{"indexed":false,"internalType":"uint256","name":"tokensBought","type":"uint256"},{"indexed":false,"internalType":"uint128","name":"soldId","type":"uint128"},{"indexed":false,"internalType":"uint128","name":"boughtId","type":"uint128"}],"name":"TokenSwapUnderlying","type":"event"},{"anonymous":false,"inputs":[{"indexed":false,"internalType":"address","name":"account","type":"address"}],"name":"Unpaused","type":"event"},{"inputs":[{"internalType":"uint256[]","name":"amounts","type":"uint256[]"},{"internalType":"uint256","name":"minToMint","type":"uint256"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"addLiquidity","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"user","type":"address"}],"name":"calculateCurrentWithdrawFee","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"account","type":"address"},{"internalType":"uint256","name":"amount","type":"uint256"}],"name":"calculateRemoveLiquidity","outputs":[{"internalType":"uint256[]","name":"","type":"uint256[]"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"account","type":"address"},{"internalType":"uint256","name":"tokenAmount","type":"uint256"},{"internalType":"uint8","name":"tokenIndex","type":"uint8"}],"name":"calculateRemoveLiquidityOneToken","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint8","name":"tokenIndexFrom","type":"uint8"},{"internalType":"uint8","name":"tokenIndexTo","type":"uint8"},{"internalType":"uint256","name":"dx","type":"uint256"}],"name":"calculateSwap","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint8","name":"tokenIndexFrom","type":"uint8"},{"internalType":"uint8","name":"tokenIndexTo","type":"uint8"},{"internalType":"uint256","name":"dx","type":"uint256"}],"name":"calculateSwapUnderlying","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"account","type":"address"},{"internalType":"uint256[]","name":"amounts","type":"uint256[]"},{"internalType":"bool","name":"deposit","type":"bool"}],"name":"calculateTokenAmount","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"getA","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"getAPrecise","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"index","type":"uint256"}],"name":"getAdminBalance","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"user","type":"address"}],"name":"getDepositTimestamp","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint8","name":"index","type":"uint8"}],"name":"getToken","outputs":[{"internalType":"contract IERC20","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint8","name":"index","type":"uint8"}],"name":"getTokenBalance","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"tokenAddress","type":"address"}],"name":"getTokenIndex","outputs":[{"internalType":"uint8","name":"","type":"uint8"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"getVirtualPrice","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"contract IERC20[]","name":"_pooledTokens","type":"address[]"},{"internalType":"uint8[]","name":"decimals","type":"uint8[]"},{"internalType":"string","name":"lpTokenName","type":"string"},{"internalType":"string","name":"lpTokenSymbol","type":"string"},{"internalType":"uint256","name":"_a","type":"uint256"},{"internalType":"uint256","name":"_fee","type":"uint256"},{"internalType":"uint256","name":"_adminFee","type":"uint256"},{"internalType":"uint256","name":"_depositFee","type":"uint256"},{"internalType":"uint256","name":"_withdrawFee","type":"uint256"},{"internalType":"address","name":"_devaddr","type":"address"}],"name":"initialize","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"contract IERC20[]","name":"_pooledTokens","type":"address[]"},{"internalType":"uint8[]","name":"decimals","type":"uint8[]"},{"internalType":"string","name":"lpTokenName","type":"string"},{"internalType":"string","name":"lpTokenSymbol","type":"string"},{"internalType":"uint256","name":"_a","type":"uint256"},{"internalType":"uint256","name":"_fee","type":"uint256"},{"internalType":"uint256","name":"_adminFee","type":"uint256"},{"internalType":"uint256","name":"_depositFee","type":"uint256"},{"internalType":"uint256","name":"_withdrawFee","type":"uint256"},{"internalType":"address","name":"_devaddr","type":"address"},{"internalType":"contract ISwap","name":"baseSwap","type":"address"}],"name":"initializeMetaSwap","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"metaSwapStorage","outputs":[{"internalType":"contract ISwap","name":"baseSwap","type":"address"},{"internalType":"uint256","name":"baseVirtualPrice","type":"uint256"},{"internalType":"uint256","name":"baseCacheLastUpdated","type":"uint256"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[],"name":"pause","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"paused","outputs":[{"internalType":"bool","name":"","type":"bool"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint256","name":"futureA","type":"uint256"},{"internalType":"uint256","name":"futureTime","type":"uint256"}],"name":"rampA","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"amount","type":"uint256"},{"internalType":"uint256[]","name":"minAmounts","type":"uint256[]"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"removeLiquidity","outputs":[{"internalType":"uint256[]","name":"","type":"uint256[]"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256[]","name":"amounts","type":"uint256[]"},{"internalType":"uint256","name":"maxBurnAmount","type":"uint256"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"removeLiquidityImbalance","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"tokenAmount","type":"uint256"},{"internalType":"uint8","name":"tokenIndex","type":"uint8"},{"internalType":"uint256","name":"minAmount","type":"uint256"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"removeLiquidityOneToken","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"renounceOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"newAdminFee","type":"uint256"}],"name":"setAdminFee","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"newDepositFee","type":"uint256"}],"name":"setDefaultDepositFee","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"newWithdrawFee","type":"uint256"}],"name":"setDefaultWithdrawFee","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"_devaddr","type":"address"}],"name":"setDevAddress","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint256","name":"newSwapFee","type":"uint256"}],"name":"setSwapFee","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"stopRampA","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"uint8","name":"tokenIndexFrom","type":"uint8"},{"internalType":"uint8","name":"tokenIndexTo","type":"uint8"},{"internalType":"uint256","name":"dx","type":"uint256"},{"internalType":"uint256","name":"minDy","type":"uint256"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"swap","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"swapStorage","outputs":[{"internalType":"uint256","name":"initialA","type":"uint256"},{"internalType":"uint256","name":"futureA","type":"uint256"},{"internalType":"uint256","name":"initialATime","type":"uint256"},{"internalType":"uint256","name":"futureATime","type":"uint256"},{"internalType":"uint256","name":"swapFee","type":"uint256"},{"internalType":"uint256","name":"adminFee","type":"uint256"},{"internalType":"uint256","name":"defaultDepositFee","type":"uint256"},{"internalType":"uint256","name":"defaultWithdrawFee","type":"uint256"},{"internalType":"contract LPToken","name":"lpToken","type":"address"},{"internalType":"address","name":"devaddr","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"uint8","name":"tokenIndexFrom","type":"uint8"},{"internalType":"uint8","name":"tokenIndexTo","type":"uint8"},{"internalType":"uint256","name":"dx","type":"uint256"},{"internalType":"uint256","name":"minDy","type":"uint256"},{"internalType":"uint256","name":"deadline","type":"uint256"}],"name":"swapUnderlying","outputs":[{"internalType":"uint256","name":"","type":"uint256"}],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"newOwner","type":"address"}],"name":"transferOwnership","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"unpause","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"address","name":"recipient","type":"address"},{"internalType":"uint256","name":"transferAmount","type":"uint256"}],"name":"updateUserWithdrawFee","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"withdrawAdminFees","outputs":[],"stateMutability":"nonpayable","type":"function"}]

Block Transaction Gas Used Reward
Age Block Fee Address BC Fee Address Voting Power Jailed Incoming
Block Uncle Number Difficulty Gas Used Reward
Loading
Loading
Make sure to use the "Vote Down" button for any spammy posts, and the "Vote Up" for interesting conversations.