swapdata.json

{"flattened_source": "// SPDX-License-Identifier: MIT\n\npragma solidity 0.6.12;\n\n\n\n// Part: Address\n\n/**\n * @dev Collection of functions related to the address type\n */\nlibrary Address {\n    /**\n     * @dev Returns true if `account` is a contract.\n     *\n     * [IMPORTANT]\n     * ====\n     * It is unsafe to assume that an address for which this function returns\n     * false is an externally-owned account (EOA) and not a contract.\n     *\n     * Among others, `isContract` will return false for the following\n     * types of addresses:\n     *\n     *  - an externally-owned account\n     *  - a contract in construction\n     *  - an address where a contract will be created\n     *  - an address where a contract lived, but was destroyed\n     * ====\n     */\n    function isContract(address account) internal view returns (bool) {\n        // This method relies on extcodesize, which returns 0 for contracts in\n        // construction, since the code is only stored at the end of the\n        // constructor execution.\n\n        uint256 size;\n        // solhint-disable-next-line no-inline-assembly\n        assembly { size := extcodesize(account) }\n        return size > 0;\n    }\n\n    /**\n     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to\n     * `recipient`, forwarding all available gas and reverting on errors.\n     *\n     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost\n     * of certain opcodes, possibly making contracts go over the 2300 gas limit\n     * imposed by `transfer`, making them unable to receive funds via\n     * `transfer`. {sendValue} removes this limitation.\n     *\n     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].\n     *\n     * IMPORTANT: because control is transferred to `recipient`, care must be\n     * taken to not create reentrancy vulnerabilities. Consider using\n     * {ReentrancyGuard} or the\n     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].\n     */\n    function sendValue(address payable recipient, uint256 amount) internal {\n        require(address(this).balance >= amount, \"Address: insufficient balance\");\n\n        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value\n        (bool success, ) = recipient.call{ value: amount }(\"\");\n        require(success, \"Address: unable to send value, recipient may have reverted\");\n    }\n\n    /**\n     * @dev Performs a Solidity function call using a low level `call`. A\n     * plain`call` is an unsafe replacement for a function call: use this\n     * function instead.\n     *\n     * If `target` reverts with a revert reason, it is bubbled up by this\n     * function (like regular Solidity function calls).\n     *\n     * Returns the raw returned data. To convert to the expected return value,\n     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].\n     *\n     * Requirements:\n     *\n     * - `target` must be a contract.\n     * - calling `target` with `data` must not revert.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(address target, bytes memory data) internal returns (bytes memory) {\n      return functionCall(target, data, \"Address: low-level call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with\n     * `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, 0, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but also transferring `value` wei to `target`.\n     *\n     * Requirements:\n     *\n     * - the calling contract must have an ETH balance of at least `value`.\n     * - the called Solidity function must be `payable`.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {\n        return functionCallWithValue(target, data, value, \"Address: low-level call with value failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but\n     * with `errorMessage` as a fallback revert reason when `target` reverts.\n     *\n     * _Available since v3.1._\n     */\n    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {\n        require(address(this).balance >= value, \"Address: insufficient balance for call\");\n        require(isContract(target), \"Address: call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.call{ value: value }(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {\n        return functionStaticCall(target, data, \"Address: low-level static call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a static call.\n     *\n     * _Available since v3.3._\n     */\n    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {\n        require(isContract(target), \"Address: static call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.staticcall(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {\n        return functionDelegateCall(target, data, \"Address: low-level delegate call failed\");\n    }\n\n    /**\n     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],\n     * but performing a delegate call.\n     *\n     * _Available since v3.4._\n     */\n    function functionDelegateCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {\n        require(isContract(target), \"Address: delegate call to non-contract\");\n\n        // solhint-disable-next-line avoid-low-level-calls\n        (bool success, bytes memory returndata) = target.delegatecall(data);\n        return _verifyCallResult(success, returndata, errorMessage);\n    }\n\n    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {\n        if (success) {\n            return returndata;\n        } else {\n            // Look for revert reason and bubble it up if present\n            if (returndata.length > 0) {\n                // The easiest way to bubble the revert reason is using memory via assembly\n\n                // solhint-disable-next-line no-inline-assembly\n                assembly {\n                    let returndata_size := mload(returndata)\n                    revert(add(32, returndata), returndata_size)\n                }\n            } else {\n                revert(errorMessage);\n            }\n        }\n    }\n}\n\n// Part: Context\n\n/*\n * @dev Provides information about the current execution context, including the\n * sender of the transaction and its data. While these are generally available\n * via msg.sender and msg.data, they should not be accessed in such a direct\n * manner, since when dealing with GSN meta-transactions the account sending and\n * paying for execution may not be the actual sender (as far as an application\n * is concerned).\n *\n * This contract is only required for intermediate, library-like contracts.\n */\nabstract contract Context {\n    function _msgSender() internal view virtual returns (address payable) {\n        return msg.sender;\n    }\n\n    function _msgData() internal view virtual returns (bytes memory) {\n        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691\n        return msg.data;\n    }\n}\n\n// Part: IERC20\n\n/**\n * @dev Interface of the ERC20 standard as defined in the EIP.\n */\ninterface IERC20 {\n    /**\n     * @dev Returns the amount of tokens in existence.\n     */\n    function totalSupply() external view returns (uint256);\n\n    /**\n     * @dev Returns the amount of tokens owned by `account`.\n     */\n    function balanceOf(address account) external view returns (uint256);\n\n    /**\n     * @dev Moves `amount` tokens from the caller's account to `recipient`.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transfer(address recipient, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Returns the remaining number of tokens that `spender` will be\n     * allowed to spend on behalf of `owner` through {transferFrom}. This is\n     * zero by default.\n     *\n     * This value changes when {approve} or {transferFrom} are called.\n     */\n    function allowance(address owner, address spender) external view returns (uint256);\n\n    /**\n     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * IMPORTANT: Beware that changing an allowance with this method brings the risk\n     * that someone may use both the old and the new allowance by unfortunate\n     * transaction ordering. One possible solution to mitigate this race\n     * condition is to first reduce the spender's allowance to 0 and set the\n     * desired value afterwards:\n     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729\n     *\n     * Emits an {Approval} event.\n     */\n    function approve(address spender, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Moves `amount` tokens from `sender` to `recipient` using the\n     * allowance mechanism. `amount` is then deducted from the caller's\n     * allowance.\n     *\n     * Returns a boolean value indicating whether the operation succeeded.\n     *\n     * Emits a {Transfer} event.\n     */\n    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);\n\n    /**\n     * @dev Emitted when `value` tokens are moved from one account (`from`) to\n     * another (`to`).\n     *\n     * Note that `value` may be zero.\n     */\n    event Transfer(address indexed from, address indexed to, uint256 value);\n\n    /**\n     * @dev Emitted when the allowance of a `spender` for an `owner` is set by\n     * a call to {approve}. `value` is the new allowance.\n     */\n    event Approval(address indexed owner, address indexed spender, uint256 value);\n}\n\n// Part: MathUtils\n\n/**\n * @title MathUtils library\n * @notice A library to be used in conjunction with SafeMath. Contains functions for calculating\n * differences between two uint256.\n */\nlibrary MathUtils {\n    /**\n     * @notice Compares a and b and returns true if the difference between a and b\n     *         is less than 1 or equal to each other.\n     * @param a uint256 to compare with\n     * @param b uint256 to compare with\n     * @return True if the difference between a and b is less than 1 or equal,\n     *         otherwise return false\n     */\n    function within1(uint256 a, uint256 b) external pure returns (bool) {\n        return (_difference(a, b) <= 1);\n    }\n\n    /**\n     * @notice Calculates absolute difference between a and b\n     * @param a uint256 to compare with\n     * @param b uint256 to compare with\n     * @return Difference between a and b\n     */\n    function difference(uint256 a, uint256 b) external pure returns (uint256) {\n        return _difference(a, b);\n    }\n\n    /**\n     * @notice Calculates absolute difference between a and b\n     * @param a uint256 to compare with\n     * @param b uint256 to compare with\n     * @return Difference between a and b\n     */\n    function _difference(uint256 a, uint256 b) internal pure returns (uint256) {\n        if (a > b) {\n            return a - b;\n        }\n        return b - a;\n    }\n}\n\n// Part: ReentrancyGuard\n\n/**\n * @dev Contract module that helps prevent reentrant calls to a function.\n *\n * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier\n * available, which can be applied to functions to make sure there are no nested\n * (reentrant) calls to them.\n *\n * Note that because there is a single `nonReentrant` guard, functions marked as\n * `nonReentrant` may not call one another. This can be worked around by making\n * those functions `private`, and then adding `external` `nonReentrant` entry\n * points to them.\n *\n * TIP: If you would like to learn more about reentrancy and alternative ways\n * to protect against it, check out our blog post\n * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].\n */\nabstract contract ReentrancyGuard {\n    // Booleans are more expensive than uint256 or any type that takes up a full\n    // word because each write operation emits an extra SLOAD to first read the\n    // slot's contents, replace the bits taken up by the boolean, and then write\n    // back. This is the compiler's defense against contract upgrades and\n    // pointer aliasing, and it cannot be disabled.\n\n    // The values being non-zero value makes deployment a bit more expensive,\n    // but in exchange the refund on every call to nonReentrant will be lower in\n    // amount. Since refunds are capped to a percentage of the total\n    // transaction's gas, it is best to keep them low in cases like this one, to\n    // increase the likelihood of the full refund coming into effect.\n    uint256 private constant _NOT_ENTERED = 1;\n    uint256 private constant _ENTERED = 2;\n\n    uint256 private _status;\n\n    constructor () internal {\n        _status = _NOT_ENTERED;\n    }\n\n    /**\n     * @dev Prevents a contract from calling itself, directly or indirectly.\n     * Calling a `nonReentrant` function from another `nonReentrant`\n     * function is not supported. It is possible to prevent this from happening\n     * by making the `nonReentrant` function external, and make it call a\n     * `private` function that does the actual work.\n     */\n    modifier nonReentrant() {\n        // On the first call to nonReentrant, _notEntered will be true\n        require(_status != _ENTERED, \"ReentrancyGuard: reentrant call\");\n\n        // Any calls to nonReentrant after this point will fail\n        _status = _ENTERED;\n\n        _;\n\n        // By storing the original value once again, a refund is triggered (see\n        // https://eips.ethereum.org/EIPS/eip-2200)\n        _status = _NOT_ENTERED;\n    }\n}\n\n// Part: SafeMath\n\n/**\n * @dev Wrappers over Solidity's arithmetic operations with added overflow\n * checks.\n *\n * Arithmetic operations in Solidity wrap on overflow. This can easily result\n * in bugs, because programmers usually assume that an overflow raises an\n * error, which is the standard behavior in high level programming languages.\n * `SafeMath` restores this intuition by reverting the transaction when an\n * operation overflows.\n *\n * Using this library instead of the unchecked operations eliminates an entire\n * class of bugs, so it's recommended to use it always.\n */\nlibrary SafeMath {\n    /**\n     * @dev Returns the addition of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        uint256 c = a + b;\n        if (c < a) return (false, 0);\n        return (true, c);\n    }\n\n    /**\n     * @dev Returns the substraction of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b > a) return (false, 0);\n        return (true, a - b);\n    }\n\n    /**\n     * @dev Returns the multiplication of two unsigned integers, with an overflow flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the\n        // benefit is lost if 'b' is also tested.\n        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522\n        if (a == 0) return (true, 0);\n        uint256 c = a * b;\n        if (c / a != b) return (false, 0);\n        return (true, c);\n    }\n\n    /**\n     * @dev Returns the division of two unsigned integers, with a division by zero flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b == 0) return (false, 0);\n        return (true, a / b);\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.\n     *\n     * _Available since v3.4._\n     */\n    function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {\n        if (b == 0) return (false, 0);\n        return (true, a % b);\n    }\n\n    /**\n     * @dev Returns the addition of two unsigned integers, reverting on\n     * overflow.\n     *\n     * Counterpart to Solidity's `+` operator.\n     *\n     * Requirements:\n     *\n     * - Addition cannot overflow.\n     */\n    function add(uint256 a, uint256 b) internal pure returns (uint256) {\n        uint256 c = a + b;\n        require(c >= a, \"SafeMath: addition overflow\");\n        return c;\n    }\n\n    /**\n     * @dev Returns the subtraction of two unsigned integers, reverting on\n     * overflow (when the result is negative).\n     *\n     * Counterpart to Solidity's `-` operator.\n     *\n     * Requirements:\n     *\n     * - Subtraction cannot overflow.\n     */\n    function sub(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b <= a, \"SafeMath: subtraction overflow\");\n        return a - b;\n    }\n\n    /**\n     * @dev Returns the multiplication of two unsigned integers, reverting on\n     * overflow.\n     *\n     * Counterpart to Solidity's `*` operator.\n     *\n     * Requirements:\n     *\n     * - Multiplication cannot overflow.\n     */\n    function mul(uint256 a, uint256 b) internal pure returns (uint256) {\n        if (a == 0) return 0;\n        uint256 c = a * b;\n        require(c / a == b, \"SafeMath: multiplication overflow\");\n        return c;\n    }\n\n    /**\n     * @dev Returns the integer division of two unsigned integers, reverting on\n     * division by zero. The result is rounded towards zero.\n     *\n     * Counterpart to Solidity's `/` operator. Note: this function uses a\n     * `revert` opcode (which leaves remaining gas untouched) while Solidity\n     * uses an invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function div(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b > 0, \"SafeMath: division by zero\");\n        return a / b;\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n     * reverting when dividing by zero.\n     *\n     * Counterpart to Solidity's `%` operator. This function uses a `revert`\n     * opcode (which leaves remaining gas untouched) while Solidity uses an\n     * invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function mod(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b > 0, \"SafeMath: modulo by zero\");\n        return a % b;\n    }\n\n    /**\n     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on\n     * overflow (when the result is negative).\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {trySub}.\n     *\n     * Counterpart to Solidity's `-` operator.\n     *\n     * Requirements:\n     *\n     * - Subtraction cannot overflow.\n     */\n    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b <= a, errorMessage);\n        return a - b;\n    }\n\n    /**\n     * @dev Returns the integer division of two unsigned integers, reverting with custom message on\n     * division by zero. The result is rounded towards zero.\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {tryDiv}.\n     *\n     * Counterpart to Solidity's `/` operator. Note: this function uses a\n     * `revert` opcode (which leaves remaining gas untouched) while Solidity\n     * uses an invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b > 0, errorMessage);\n        return a / b;\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n     * reverting with custom message when dividing by zero.\n     *\n     * CAUTION: This function is deprecated because it requires allocating memory for the error\n     * message unnecessarily. For custom revert reasons use {tryMod}.\n     *\n     * Counterpart to Solidity's `%` operator. This function uses a `revert`\n     * opcode (which leaves remaining gas untouched) while Solidity uses an\n     * invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b > 0, errorMessage);\n        return a % b;\n    }\n}\n\n// Part: ERC20\n\n/**\n * @dev Implementation of the {IERC20} interface.\n *\n * This implementation is agnostic to the way tokens are created. This means\n * that a supply mechanism has to be added in a derived contract using {_mint}.\n * For a generic mechanism see {ERC20PresetMinterPauser}.\n *\n * TIP: For a detailed writeup see our guide\n * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How\n * to implement supply mechanisms].\n *\n * We have followed general OpenZeppelin guidelines: functions revert instead\n * of returning `false` on failure. This behavior is nonetheless conventional\n * and does not conflict with the expectations of ERC20 applications.\n *\n * Additionally, an {Approval} event is emitted on calls to {transferFrom}.\n * This allows applications to reconstruct the allowance for all accounts just\n * by listening to said events. Other implementations of the EIP may not emit\n * these events, as it isn't required by the specification.\n *\n * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}\n * functions have been added to mitigate the well-known issues around setting\n * allowances. See {IERC20-approve}.\n */\ncontract ERC20 is Context, IERC20 {\n    using SafeMath for uint256;\n\n    mapping (address => uint256) private _balances;\n\n    mapping (address => mapping (address => uint256)) private _allowances;\n\n    uint256 private _totalSupply;\n\n    string private _name;\n    string private _symbol;\n    uint8 private _decimals;\n\n    /**\n     * @dev Sets the values for {name} and {symbol}, initializes {decimals} with\n     * a default value of 18.\n     *\n     * To select a different value for {decimals}, use {_setupDecimals}.\n     *\n     * All three of these values are immutable: they can only be set once during\n     * construction.\n     */\n    constructor (string memory name_, string memory symbol_) public {\n        _name = name_;\n        _symbol = symbol_;\n        _decimals = 18;\n    }\n\n    /**\n     * @dev Returns the name of the token.\n     */\n    function name() public view virtual returns (string memory) {\n        return _name;\n    }\n\n    /**\n     * @dev Returns the symbol of the token, usually a shorter version of the\n     * name.\n     */\n    function symbol() public view virtual returns (string memory) {\n        return _symbol;\n    }\n\n    /**\n     * @dev Returns the number of decimals used to get its user representation.\n     * For example, if `decimals` equals `2`, a balance of `505` tokens should\n     * be displayed to a user as `5,05` (`505 / 10 ** 2`).\n     *\n     * Tokens usually opt for a value of 18, imitating the relationship between\n     * Ether and Wei. This is the value {ERC20} uses, unless {_setupDecimals} is\n     * called.\n     *\n     * NOTE: This information is only used for _display_ purposes: it in\n     * no way affects any of the arithmetic of the contract, including\n     * {IERC20-balanceOf} and {IERC20-transfer}.\n     */\n    function decimals() public view virtual returns (uint8) {\n        return _decimals;\n    }\n\n    /**\n     * @dev See {IERC20-totalSupply}.\n     */\n    function totalSupply() public view virtual override returns (uint256) {\n        return _totalSupply;\n    }\n\n    /**\n     * @dev See {IERC20-balanceOf}.\n     */\n    function balanceOf(address account) public view virtual override returns (uint256) {\n        return _balances[account];\n    }\n\n    /**\n     * @dev See {IERC20-transfer}.\n     *\n     * Requirements:\n     *\n     * - `recipient` cannot be the zero address.\n     * - the caller must have a balance of at least `amount`.\n     */\n    function transfer(address recipient, uint256 amount) public virtual override returns (bool) {\n        _transfer(_msgSender(), recipient, amount);\n        return true;\n    }\n\n    /**\n     * @dev See {IERC20-allowance}.\n     */\n    function allowance(address owner, address spender) public view virtual override returns (uint256) {\n        return _allowances[owner][spender];\n    }\n\n    /**\n     * @dev See {IERC20-approve}.\n     *\n     * Requirements:\n     *\n     * - `spender` cannot be the zero address.\n     */\n    function approve(address spender, uint256 amount) public virtual override returns (bool) {\n        _approve(_msgSender(), spender, amount);\n        return true;\n    }\n\n    /**\n     * @dev See {IERC20-transferFrom}.\n     *\n     * Emits an {Approval} event indicating the updated allowance. This is not\n     * required by the EIP. See the note at the beginning of {ERC20}.\n     *\n     * Requirements:\n     *\n     * - `sender` and `recipient` cannot be the zero address.\n     * - `sender` must have a balance of at least `amount`.\n     * - the caller must have allowance for ``sender``'s tokens of at least\n     * `amount`.\n     */\n    function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) {\n        _transfer(sender, recipient, amount);\n        _approve(sender, _msgSender(), _allowances[sender][_msgSender()].sub(amount, \"ERC20: transfer amount exceeds allowance\"));\n        return true;\n    }\n\n    /**\n     * @dev Atomically increases the allowance granted to `spender` by the caller.\n     *\n     * This is an alternative to {approve} that can be used as a mitigation for\n     * problems described in {IERC20-approve}.\n     *\n     * Emits an {Approval} event indicating the updated allowance.\n     *\n     * Requirements:\n     *\n     * - `spender` cannot be the zero address.\n     */\n    function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {\n        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].add(addedValue));\n        return true;\n    }\n\n    /**\n     * @dev Atomically decreases the allowance granted to `spender` by the caller.\n     *\n     * This is an alternative to {approve} that can be used as a mitigation for\n     * problems described in {IERC20-approve}.\n     *\n     * Emits an {Approval} event indicating the updated allowance.\n     *\n     * Requirements:\n     *\n     * - `spender` cannot be the zero address.\n     * - `spender` must have allowance for the caller of at least\n     * `subtractedValue`.\n     */\n    function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {\n        _approve(_msgSender(), spender, _allowances[_msgSender()][spender].sub(subtractedValue, \"ERC20: decreased allowance below zero\"));\n        return true;\n    }\n\n    /**\n     * @dev Moves tokens `amount` from `sender` to `recipient`.\n     *\n     * This is internal function is equivalent to {transfer}, and can be used to\n     * e.g. implement automatic token fees, slashing mechanisms, etc.\n     *\n     * Emits a {Transfer} event.\n     *\n     * Requirements:\n     *\n     * - `sender` cannot be the zero address.\n     * - `recipient` cannot be the zero address.\n     * - `sender` must have a balance of at least `amount`.\n     */\n    function _transfer(address sender, address recipient, uint256 amount) internal virtual {\n        require(sender != address(0), \"ERC20: transfer from the zero address\");\n        require(recipient != address(0), \"ERC20: transfer to the zero address\");\n\n        _beforeTokenTransfer(sender, recipient, amount);\n\n        _balances[sender] = _balances[sender].sub(amount, \"ERC20: transfer amount exceeds balance\");\n        _balances[recipient] = _balances[recipient].add(amount);\n        emit Transfer(sender, recipient, amount);\n    }\n\n    /** @dev Creates `amount` tokens and assigns them to `account`, increasing\n     * the total supply.\n     *\n     * Emits a {Transfer} event with `from` set to the zero address.\n     *\n     * Requirements:\n     *\n     * - `to` cannot be the zero address.\n     */\n    function _mint(address account, uint256 amount) internal virtual {\n        require(account != address(0), \"ERC20: mint to the zero address\");\n\n        _beforeTokenTransfer(address(0), account, amount);\n\n        _totalSupply = _totalSupply.add(amount);\n        _balances[account] = _balances[account].add(amount);\n        emit Transfer(address(0), account, amount);\n    }\n\n    /**\n     * @dev Destroys `amount` tokens from `account`, reducing the\n     * total supply.\n     *\n     * Emits a {Transfer} event with `to` set to the zero address.\n     *\n     * Requirements:\n     *\n     * - `account` cannot be the zero address.\n     * - `account` must have at least `amount` tokens.\n     */\n    function _burn(address account, uint256 amount) internal virtual {\n        require(account != address(0), \"ERC20: burn from the zero address\");\n\n        _beforeTokenTransfer(account, address(0), amount);\n\n        _balances[account] = _balances[account].sub(amount, \"ERC20: burn amount exceeds balance\");\n        _totalSupply = _totalSupply.sub(amount);\n        emit Transfer(account, address(0), amount);\n    }\n\n    /**\n     * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.\n     *\n     * This internal function is equivalent to `approve`, and can be used to\n     * e.g. set automatic allowances for certain subsystems, etc.\n     *\n     * Emits an {Approval} event.\n     *\n     * Requirements:\n     *\n     * - `owner` cannot be the zero address.\n     * - `spender` cannot be the zero address.\n     */\n    function _approve(address owner, address spender, uint256 amount) internal virtual {\n        require(owner != address(0), \"ERC20: approve from the zero address\");\n        require(spender != address(0), \"ERC20: approve to the zero address\");\n\n        _allowances[owner][spender] = amount;\n        emit Approval(owner, spender, amount);\n    }\n\n    /**\n     * @dev Sets {decimals} to a value other than the default one of 18.\n     *\n     * WARNING: This function should only be called from the constructor. Most\n     * applications that interact with token contracts will not expect\n     * {decimals} to ever change, and may work incorrectly if it does.\n     */\n    function _setupDecimals(uint8 decimals_) internal virtual {\n        _decimals = decimals_;\n    }\n\n    /**\n     * @dev Hook that is called before any transfer of tokens. This includes\n     * minting and burning.\n     *\n     * Calling conditions:\n     *\n     * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens\n     * will be to transferred to `to`.\n     * - when `from` is zero, `amount` tokens will be minted for `to`.\n     * - when `to` is zero, `amount` of ``from``'s tokens will be burned.\n     * - `from` and `to` are never both zero.\n     *\n     * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].\n     */\n    function _beforeTokenTransfer(address from, address to, uint256 amount) internal virtual { }\n}\n\n// Part: ISwap\n\ninterface ISwap {\n    // pool data view functions\n    function getA() external view returns (uint256);\n\n    function getToken(uint8 index) external view returns (IERC20);\n\n    function getTokenIndex(address tokenAddress) external view returns (uint8);\n\n    function getTokenBalance(uint8 index) external view returns (uint256);\n\n    function getVirtualPrice() external view returns (uint256);\n\n    // min return calculation functions\n    function calculateSwap(\n        uint8 tokenIndexFrom,\n        uint8 tokenIndexTo,\n        uint256 dx\n    ) external view returns (uint256);\n\n    function calculateTokenAmount(\n        address account,\n        uint256[] calldata amounts,\n        bool deposit\n    ) external view returns (uint256);\n\n    function calculateRemoveLiquidity(address account, uint256 amount)\n        external\n        view\n        returns (uint256[] memory);\n\n    function calculateRemoveLiquidityOneToken(\n        address account,\n        uint256 tokenAmount,\n        uint8 tokenIndex\n    ) external view returns (uint256 availableTokenAmount);\n\n    // state modifying functions\n    function initialize(\n        IERC20[] memory pooledTokens,\n        uint8[] memory decimals,\n        string memory lpTokenName,\n        string memory lpTokenSymbol,\n        uint256 a,\n        uint256 fee,\n        uint256 adminFee,\n        uint256 depositFee,\n        uint256 withdrawFee,\n        address devaddr\n    ) external;\n\n    function swap(\n        uint8 tokenIndexFrom,\n        uint8 tokenIndexTo,\n        uint256 dx,\n        uint256 minDy,\n        uint256 deadline\n    ) external returns (uint256);\n\n    function addLiquidity(\n        uint256[] calldata amounts,\n        uint256 minToMint,\n        uint256 deadline\n    ) external returns (uint256);\n\n    function removeLiquidity(\n        uint256 amount,\n        uint256[] calldata minAmounts,\n        uint256 deadline\n    ) external returns (uint256[] memory);\n\n    function removeLiquidityOneToken(\n        uint256 tokenAmount,\n        uint8 tokenIndex,\n        uint256 minAmount,\n        uint256 deadline\n    ) external returns (uint256);\n\n    function removeLiquidityImbalance(\n        uint256[] calldata amounts,\n        uint256 maxBurnAmount,\n        uint256 deadline\n    ) external returns (uint256);\n\n    // withdraw fee update function\n    function updateUserWithdrawFee(address recipient, uint256 transferAmount)\n        external;\n}\n\n// Part: Ownable\n\n/**\n * @dev Contract module which provides a basic access control mechanism, where\n * there is an account (an owner) that can be granted exclusive access to\n * specific functions.\n *\n * By default, the owner account will be the one that deploys the contract. This\n * can later be changed with {transferOwnership}.\n *\n * This module is used through inheritance. It will make available the modifier\n * `onlyOwner`, which can be applied to your functions to restrict their use to\n * the owner.\n */\nabstract contract Ownable is Context {\n    address private _owner;\n\n    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);\n\n    /**\n     * @dev Initializes the contract setting the deployer as the initial owner.\n     */\n    constructor () internal {\n        address msgSender = _msgSender();\n        _owner = msgSender;\n        emit OwnershipTransferred(address(0), msgSender);\n    }\n\n    /**\n     * @dev Returns the address of the current owner.\n     */\n    function owner() public view virtual returns (address) {\n        return _owner;\n    }\n\n    /**\n     * @dev Throws if called by any account other than the owner.\n     */\n    modifier onlyOwner() {\n        require(owner() == _msgSender(), \"Ownable: caller is not the owner\");\n        _;\n    }\n\n    /**\n     * @dev Leaves the contract without owner. It will not be possible to call\n     * `onlyOwner` functions anymore. Can only be called by the current owner.\n     *\n     * NOTE: Renouncing ownership will leave the contract without an owner,\n     * thereby removing any functionality that is only available to the owner.\n     */\n    function renounceOwnership() public virtual onlyOwner {\n        emit OwnershipTransferred(_owner, address(0));\n        _owner = address(0);\n    }\n\n    /**\n     * @dev Transfers ownership of the contract to a new account (`newOwner`).\n     * Can only be called by the current owner.\n     */\n    function transferOwnership(address newOwner) public virtual onlyOwner {\n        require(newOwner != address(0), \"Ownable: new owner is the zero address\");\n        emit OwnershipTransferred(_owner, newOwner);\n        _owner = newOwner;\n    }\n}\n\n// Part: Pausable\n\n/**\n * @dev Contract module which allows children to implement an emergency stop\n * mechanism that can be triggered by an authorized account.\n *\n * This module is used through inheritance. It will make available the\n * modifiers `whenNotPaused` and `whenPaused`, which can be applied to\n * the functions of your contract. Note that they will not be pausable by\n * simply including this module, only once the modifiers are put in place.\n */\nabstract contract Pausable is Context {\n    /**\n     * @dev Emitted when the pause is triggered by `account`.\n     */\n    event Paused(address account);\n\n    /**\n     * @dev Emitted when the pause is lifted by `account`.\n     */\n    event Unpaused(address account);\n\n    bool private _paused;\n\n    /**\n     * @dev Initializes the contract in unpaused state.\n     */\n    constructor () internal {\n        _paused = false;\n    }\n\n    /**\n     * @dev Returns true if the contract is paused, and false otherwise.\n     */\n    function paused() public view virtual returns (bool) {\n        return _paused;\n    }\n\n    /**\n     * @dev Modifier to make a function callable only when the contract is not paused.\n     *\n     * Requirements:\n     *\n     * - The contract must not be paused.\n     */\n    modifier whenNotPaused() {\n        require(!paused(), \"Pausable: paused\");\n        _;\n    }\n\n    /**\n     * @dev Modifier to make a function callable only when the contract is paused.\n     *\n     * Requirements:\n     *\n     * - The contract must be paused.\n     */\n    modifier whenPaused() {\n        require(paused(), \"Pausable: not paused\");\n        _;\n    }\n\n    /**\n     * @dev Triggers stopped state.\n     *\n     * Requirements:\n     *\n     * - The contract must not be paused.\n     */\n    function _pause() internal virtual whenNotPaused {\n        _paused = true;\n        emit Paused(_msgSender());\n    }\n\n    /**\n     * @dev Returns to normal state.\n     *\n     * Requirements:\n     *\n     * - The contract must be paused.\n     */\n    function _unpause() internal virtual whenPaused {\n        _paused = false;\n        emit Unpaused(_msgSender());\n    }\n}\n\n// Part: SafeERC20\n\n/**\n * @title SafeERC20\n * @dev Wrappers around ERC20 operations that throw on failure (when the token\n * contract returns false). Tokens that return no value (and instead revert or\n * throw on failure) are also supported, non-reverting calls are assumed to be\n * successful.\n * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,\n * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.\n */\nlibrary SafeERC20 {\n    using SafeMath for uint256;\n    using Address for address;\n\n    function safeTransfer(IERC20 token, address to, uint256 value) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));\n    }\n\n    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {\n        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));\n    }\n\n    /**\n     * @dev Deprecated. This function has issues similar to the ones found in\n     * {IERC20-approve}, and its usage is discouraged.\n     *\n     * Whenever possible, use {safeIncreaseAllowance} and\n     * {safeDecreaseAllowance} instead.\n     */\n    function safeApprove(IERC20 token, address spender, uint256 value) internal {\n        // safeApprove should only be called when setting an initial allowance,\n        // or when resetting it to zero. To increase and decrease it, use\n        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'\n        // solhint-disable-next-line max-line-length\n        require((value == 0) || (token.allowance(address(this), spender) == 0),\n            \"SafeERC20: approve from non-zero to non-zero allowance\"\n        );\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));\n    }\n\n    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {\n        uint256 newAllowance = token.allowance(address(this), spender).add(value);\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n    }\n\n    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {\n        uint256 newAllowance = token.allowance(address(this), spender).sub(value, \"SafeERC20: decreased allowance below zero\");\n        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));\n    }\n\n    /**\n     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement\n     * on the return value: the return value is optional (but if data is returned, it must not be false).\n     * @param token The token targeted by the call.\n     * @param data The call data (encoded using abi.encode or one of its variants).\n     */\n    function _callOptionalReturn(IERC20 token, bytes memory data) private {\n        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since\n        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that\n        // the target address contains contract code and also asserts for success in the low-level call.\n\n        bytes memory returndata = address(token).functionCall(data, \"SafeERC20: low-level call failed\");\n        if (returndata.length > 0) { // Return data is optional\n            // solhint-disable-next-line max-line-length\n            require(abi.decode(returndata, (bool)), \"SafeERC20: ERC20 operation did not succeed\");\n        }\n    }\n}\n\n// Part: ERC20Burnable\n\n/**\n * @dev Extension of {ERC20} that allows token holders to destroy both their own\n * tokens and those that they have an allowance for, in a way that can be\n * recognized off-chain (via event analysis).\n */\nabstract contract ERC20Burnable is Context, ERC20 {\n    using SafeMath for uint256;\n\n    /**\n     * @dev Destroys `amount` tokens from the caller.\n     *\n     * See {ERC20-_burn}.\n     */\n    function burn(uint256 amount) public virtual {\n        _burn(_msgSender(), amount);\n    }\n\n    /**\n     * @dev Destroys `amount` tokens from `account`, deducting from the caller's\n     * allowance.\n     *\n     * See {ERC20-_burn} and {ERC20-allowance}.\n     *\n     * Requirements:\n     *\n     * - the caller must have allowance for ``accounts``'s tokens of at least\n     * `amount`.\n     */\n    function burnFrom(address account, uint256 amount) public virtual {\n        uint256 decreasedAllowance = allowance(account, _msgSender()).sub(amount, \"ERC20: burn amount exceeds allowance\");\n\n        _approve(account, _msgSender(), decreasedAllowance);\n        _burn(account, amount);\n    }\n}\n\n// Part: OwnerPausable\n\n/**\n * @title OwnerPausable\n * @notice An ownable contract allows the owner to pause and unpause the\n * contract without a delay.\n * @dev Only methods using the provided modifiers will be paused.\n */\ncontract OwnerPausable is Ownable, Pausable {\n    /**\n     * @notice Pause the contract. Revert if already paused.\n     */\n    function pause() external onlyOwner {\n        Pausable._pause();\n    }\n\n    /**\n     * @notice Unpause the contract. Revert if already unpaused.\n     */\n    function unpause() external onlyOwner {\n        Pausable._unpause();\n    }\n}\n\n// Part: LPToken\n\n/**\n * @title Liquidity Provider Token\n * @notice This token is an ERC20 detailed token with added capability to be minted by the owner.\n * It is used to represent user's shares when providing liquidity to swap contracts.\n */\ncontract LPToken is ERC20Burnable, Ownable {\n    using SafeMath for uint256;\n\n    // Address of the swap contract that owns this LP token. When a user adds liquidity to the swap contract,\n    // they receive a proportionate amount of this LPToken.\n    ISwap public immutable swap;\n\n    /**\n     * @notice Deploys LPToken contract with given name, symbol, and decimals\n     * @dev the caller of this constructor will become the owner of this contract\n     * @param name_ name of this token\n     * @param symbol_ symbol of this token\n     * @param decimals_ number of decimals this token will be based on\n     */\n    constructor(\n        string memory name_,\n        string memory symbol_,\n        uint8 decimals_\n    ) public ERC20(name_, symbol_) {\n        _setupDecimals(decimals_);\n        swap = ISwap(_msgSender());\n    }\n\n    /**\n     * @notice Mints the given amount of LPToken to the recipient.\n     * @dev only owner can call this mint function\n     * @param recipient address of account to receive the tokens\n     * @param amount amount of tokens to mint\n     */\n    function mint(\n        address recipient,\n        uint256 amount\n    ) external onlyOwner {\n        require(amount != 0, \"amount == 0\");\n        _mint(recipient, amount);\n    }\n\n    /**\n     * @dev Overrides ERC20._beforeTokenTransfer() which get called on every transfers including\n     * minting and burning. This ensures that swap.updateUserWithdrawFees are called everytime.\n     */\n    function _beforeTokenTransfer(\n        address from,\n        address to,\n        uint256 amount\n    ) internal override(ERC20) {\n        super._beforeTokenTransfer(from, to, amount);\n        swap.updateUserWithdrawFee(to, amount);\n    }\n}\n\n// Part: SwapUtils\n\n/**\n * @title SwapUtils library\n * @notice A library to be used within Swap.sol. Contains functions responsible for custody and AMM functionalities.\n * @dev Contracts relying on this library must initialize SwapUtils.Swap struct then use this library\n * for SwapUtils.Swap struct. Note that this library contains both functions called by users and admins.\n * Admin functions should be protected within contracts using this library.\n */\nlibrary SwapUtils {\n    using SafeERC20 for IERC20;\n    using SafeMath for uint256;\n    using MathUtils for uint256;\n\n    /*** EVENTS ***/\n\n    event TokenSwap(\n        address indexed buyer,\n        uint256 tokensSold,\n        uint256 tokensBought,\n        uint128 soldId,\n        uint128 boughtId\n    );\n    event AddLiquidity(\n        address indexed provider,\n        uint256[] tokenAmounts,\n        uint256[] fees,\n        uint256 invariant,\n        uint256 lpTokenSupply\n    );\n    event RemoveLiquidity(\n        address indexed provider,\n        uint256[] tokenAmounts,\n        uint256 lpTokenSupply\n    );\n    event RemoveLiquidityOne(\n        address indexed provider,\n        uint256 lpTokenAmount,\n        uint256 lpTokenSupply,\n        uint256 boughtId,\n        uint256 tokensBought\n    );\n    event RemoveLiquidityImbalance(\n        address indexed provider,\n        uint256[] tokenAmounts,\n        uint256[] fees,\n        uint256 invariant,\n        uint256 lpTokenSupply\n    );\n    event NewAdminFee(uint256 newAdminFee);\n    event NewSwapFee(uint256 newSwapFee);\n    event NewWithdrawFee(uint256 newWithdrawFee);\n    event NewDepositFee(uint256 newDepositFee);\n    event RampA(\n        uint256 oldA,\n        uint256 newA,\n        uint256 initialTime,\n        uint256 futureTime\n    );\n    event StopRampA(uint256 currentA, uint256 time);\n\n    struct Swap {\n        // variables around the ramp management of A,\n        // the amplification coefficient * n * (n - 1)\n        // see https://www.curve.fi/stableswap-paper.pdf for details\n        uint256 initialA;\n        uint256 futureA;\n        uint256 initialATime;\n        uint256 futureATime;\n        // fee calculation\n        uint256 swapFee;\n        uint256 adminFee;\n        uint256 defaultDepositFee;\n        uint256 defaultWithdrawFee;\n        address devaddr;\n        LPToken lpToken;\n        // contract references for all tokens being pooled\n        IERC20[] pooledTokens;\n        // multipliers for each pooled token's precision to get to POOL_PRECISION_DECIMALS\n        // for example, TBTC has 18 decimals, so the multiplier should be 1. WBTC\n        // has 8, so the multiplier should be 10 ** 18 / 10 ** 8 => 10 ** 10\n        uint256[] tokenPrecisionMultipliers;\n        // the pool balance of each token, in the token's precision\n        // the contract's actual token balance might differ\n        uint256[] balances;\n        mapping(address => uint256) depositTimestamp;\n        mapping(address => uint256) withdrawFeeMultiplier;\n    }\n\n    // Struct storing variables used in calculations in the\n    // calculateWithdrawOneTokenDY function to avoid stack too deep errors\n    struct CalculateWithdrawOneTokenDYInfo {\n        uint256 d0;\n        uint256 d1;\n        uint256 newY;\n        uint256 feePerToken;\n        uint256 preciseA;\n    }\n\n    // Struct storing variables used in calculation in addLiquidity function\n    // to avoid stack too deep error\n    struct AddLiquidityInfo {\n        uint256 d0;\n        uint256 d1;\n        uint256 d2;\n        uint256 preciseA;\n    }\n\n    // Struct storing variables used in calculation in removeLiquidityImbalance function\n    // to avoid stack too deep error\n    struct RemoveLiquidityImbalanceInfo {\n        uint256 d0;\n        uint256 d1;\n        uint256 d2;\n        uint256 preciseA;\n    }\n\n    // the precision all pools tokens will be converted to\n    uint8 public constant POOL_PRECISION_DECIMALS = 18;\n\n    // the denominator used to calculate admin and LP fees. For example, an\n    // LP fee might be something like tradeAmount.mul(fee).div(FEE_DENOMINATOR)\n    uint256 private constant FEE_DENOMINATOR = 10**10;\n\n    // Max swap fee is 1% or 100bps of each swap\n    uint256 public constant MAX_SWAP_FEE = 10**8;\n\n    // Max adminFee is 100% of the swapFee\n    // adminFee does not add additional fee on top of swapFee\n    // Instead it takes a certain % of the swapFee. Therefore it has no impact on the\n    // users but only on the earnings of LPs\n    uint256 public constant MAX_ADMIN_FEE = 10**10;\n\n    // Max withdrawFee is 1% of the value withdrawn\n    // Fee will be redistributed to the LPs in the pool, rewarding\n    // long term providers.\n    uint256 public constant MAX_WITHDRAW_FEE = 10**8;\n\n    // Max depositFee is 1% of the value deposited\n    uint256 public constant MAX_DEPOSIT_FEE = 10**8;\n    \n    // Constant value used as max loop limit\n    uint256 private constant MAX_LOOP_LIMIT = 256;\n\n    // Constant values used in ramping A calculations\n    uint256 public constant A_PRECISION = 100;\n    uint256 public constant MAX_A = 10**6;\n    uint256 private constant MAX_A_CHANGE = 2;\n    uint256 private constant MIN_RAMP_TIME = 14 days;\n\n    /*** VIEW & PURE FUNCTIONS ***/\n\n    /**\n     * @notice Return A, the amplification coefficient * n * (n - 1)\n     * @dev See the StableSwap paper for details\n     * @param self Swap struct to read from\n     * @return A parameter\n     */\n    function getA(Swap storage self) external view returns (uint256) {\n        return _getA(self);\n    }\n\n    /**\n     * @notice Return A, the amplification coefficient * n * (n - 1)\n     * @dev See the StableSwap paper for details\n     * @param self Swap struct to read from\n     * @return A parameter\n     */\n    function _getA(Swap storage self) internal view returns (uint256) {\n        return _getAPrecise(self).div(A_PRECISION);\n    }\n\n    /**\n     * @notice Return A in its raw precision\n     * @dev See the StableSwap paper for details\n     * @param self Swap struct to read from\n     * @return A parameter in its raw precision form\n     */\n    function getAPrecise(Swap storage self) external view returns (uint256) {\n        return _getAPrecise(self);\n    }\n\n    /**\n     * @notice Calculates and returns A based on the ramp settings\n     * @dev See the StableSwap paper for details\n     * @param self Swap struct to read from\n     * @return A parameter in its raw precision form\n     */\n    function _getAPrecise(Swap storage self) internal view returns (uint256) {\n        uint256 t1 = self.futureATime; // time when ramp is finished\n        uint256 a1 = self.futureA; // final A value when ramp is finished\n\n        if (block.timestamp < t1) {\n            uint256 t0 = self.initialATime; // time when ramp is started\n            uint256 a0 = self.initialA; // initial A value when ramp is started\n            if (a1 > a0) {\n                // a0 + (a1 - a0) * (block.timestamp - t0) / (t1 - t0)\n                return\n                    a0.add(\n                        a1.sub(a0).mul(block.timestamp.sub(t0)).div(t1.sub(t0))\n                    );\n            } else {\n                // a0 - (a0 - a1) * (block.timestamp - t0) / (t1 - t0)\n                return\n                    a0.sub(\n                        a0.sub(a1).mul(block.timestamp.sub(t0)).div(t1.sub(t0))\n                    );\n            }\n        } else {\n            return a1;\n        }\n    }\n\n    /**\n     * @notice Retrieves the timestamp of last deposit made by the given address\n     * @param self Swap struct to read from\n     * @return timestamp of last deposit\n     */\n    function getDepositTimestamp(Swap storage self, address user)\n        external\n        view\n        returns (uint256)\n    {\n        return self.depositTimestamp[user];\n    }\n\n    /**\n     * @notice Calculate the dy, the amount of selected token that user receives and\n     * the fee of withdrawing in one token\n     * @param account the address that is withdrawing\n     * @param tokenAmount the amount to withdraw in the pool's precision\n     * @param tokenIndex which token will be withdrawn\n     * @param self Swap struct to read from\n     * @return the amount of token user will receive and the associated swap fee\n     */\n    function calculateWithdrawOneToken(\n        Swap storage self,\n        address account,\n        uint256 tokenAmount,\n        uint8 tokenIndex\n    ) public view returns (uint256, uint256) {\n        uint256 dy;\n        uint256 newY;\n\n        (dy, newY) = calculateWithdrawOneTokenDY(self, tokenIndex, tokenAmount);\n\n        // dy_0 (without fees)\n        // dy, dy_0 - dy\n\n        uint256 dySwapFee =\n            _xp(self)[tokenIndex]\n                .sub(newY)\n                .div(self.tokenPrecisionMultipliers[tokenIndex])\n                .sub(dy);\n\n        dy = dy\n            .mul(\n            FEE_DENOMINATOR.sub(calculateCurrentWithdrawFee(self, account))\n        )\n            .div(FEE_DENOMINATOR);\n\n        return (dy, dySwapFee);\n    }\n\n    /**\n     * @notice Calculate the dy of withdrawing in one token\n     * @param self Swap struct to read from\n     * @param tokenIndex which token will be withdrawn\n     * @param tokenAmount the amount to withdraw in the pools precision\n     * @return the d and the new y after withdrawing one token\n     */\n    function calculateWithdrawOneTokenDY(\n        Swap storage self,\n        uint8 tokenIndex,\n        uint256 tokenAmount\n    ) internal view returns (uint256, uint256) {\n        require(\n            tokenIndex < self.pooledTokens.length,\n            \"Token index out of range\"\n        );\n\n        // Get the current D, then solve the stableswap invariant\n        // y_i for D - tokenAmount\n        uint256[] memory xp = _xp(self);\n        CalculateWithdrawOneTokenDYInfo memory v =\n            CalculateWithdrawOneTokenDYInfo(0, 0, 0, 0, 0);\n        v.preciseA = _getAPrecise(self);\n        v.d0 = getD(xp, v.preciseA);\n        v.d1 = v.d0.sub(tokenAmount.mul(v.d0).div(self.lpToken.totalSupply()));\n\n        require(tokenAmount <= xp[tokenIndex], \"Withdraw exceeds available\");\n\n        v.newY = getYD(v.preciseA, tokenIndex, xp, v.d1);\n\n        uint256[] memory xpReduced = new uint256[](xp.length);\n\n        v.feePerToken = _feePerToken(self);\n        for (uint256 i = 0; i < self.pooledTokens.length; i++) {\n            uint256 xpi = xp[i];\n            // if i == tokenIndex, dxExpected = xp[i] * d1 / d0 - newY\n            // else dxExpected = xp[i] - (xp[i] * d1 / d0)\n            // xpReduced[i] -= dxExpected * fee / FEE_DENOMINATOR\n            xpReduced[i] = xpi.sub(\n                (\n                    (i == tokenIndex)\n                        ? xpi.mul(v.d1).div(v.d0).sub(v.newY)\n                        : xpi.sub(xpi.mul(v.d1).div(v.d0))\n                )\n                    .mul(v.feePerToken)\n                    .div(FEE_DENOMINATOR)\n            );\n        }\n\n        uint256 dy =\n            xpReduced[tokenIndex].sub(\n                getYD(v.preciseA, tokenIndex, xpReduced, v.d1)\n            );\n        dy = dy.sub(1).div(self.tokenPrecisionMultipliers[tokenIndex]);\n\n        return (dy, v.newY);\n    }\n\n    /**\n     * @notice Calculate the price of a token in the pool with given\n     * precision-adjusted balances and a particular D.\n     *\n     * @dev This is accomplished via solving the invariant iteratively.\n     * See the StableSwap paper and Curve.fi implementation for further details.\n     *\n     * x_1**2 + x1 * (sum' - (A*n**n - 1) * D / (A * n**n)) = D ** (n + 1) / (n ** (2 * n) * prod' * A)\n     * x_1**2 + b*x_1 = c\n     * x_1 = (x_1**2 + c) / (2*x_1 + b)\n     *\n     * @param a the amplification coefficient * n * (n - 1). See the StableSwap paper for details.\n     * @param tokenIndex Index of token we are calculating for.\n     * @param xp a precision-adjusted set of pool balances. Array should be\n     * the same cardinality as the pool.\n     * @param d the stableswap invariant\n     * @return the price of the token, in the same precision as in xp\n     */\n    function getYD(\n        uint256 a,\n        uint8 tokenIndex,\n        uint256[] memory xp,\n        uint256 d\n    ) internal pure returns (uint256) {\n        uint256 numTokens = xp.length;\n        require(tokenIndex < numTokens, \"Token not found\");\n\n        uint256 c = d;\n        uint256 s;\n        uint256 nA = a.mul(numTokens);\n\n        for (uint256 i = 0; i < numTokens; i++) {\n            if (i != tokenIndex) {\n                s = s.add(xp[i]);\n                c = c.mul(d).div(xp[i].mul(numTokens));\n                // If we were to protect the division loss we would have to keep the denominator separate\n                // and divide at the end. However this leads to overflow with large numTokens or/and D.\n                // c = c * D * D * D * ... overflow!\n            }\n        }\n        c = c.mul(d).mul(A_PRECISION).div(nA.mul(numTokens));\n\n        uint256 b = s.add(d.mul(A_PRECISION).div(nA));\n        uint256 yPrev;\n        uint256 y = d;\n        for (uint256 i = 0; i < MAX_LOOP_LIMIT; i++) {\n            yPrev = y;\n            y = y.mul(y).add(c).div(y.mul(2).add(b).sub(d));\n            if (y.within1(yPrev)) {\n                return y;\n            }\n        }\n        revert(\"Approximation did not converge\");\n    }\n\n    /**\n     * @notice Get D, the StableSwap invariant, based on a set of balances and a particular A.\n     * @param xp a precision-adjusted set of pool balances. Array should be the same cardinality\n     * as the pool.\n     * @param a the amplification coefficient * n * (n - 1) in A_PRECISION.\n     * See the StableSwap paper for details\n     * @return the invariant, at the precision of the pool\n     */\n    function getD(uint256[] memory xp, uint256 a)\n        internal\n        pure\n        returns (uint256)\n    {\n        uint256 numTokens = xp.length;\n        uint256 s;\n        for (uint256 i = 0; i < numTokens; i++) {\n            s = s.add(xp[i]);\n        }\n        if (s == 0) {\n            return 0;\n        }\n\n        uint256 prevD;\n        uint256 d = s;\n        uint256 nA = a.mul(numTokens);\n\n        for (uint256 i = 0; i < MAX_LOOP_LIMIT; i++) {\n            uint256 dP = d;\n            for (uint256 j = 0; j < numTokens; j++) {\n                dP = dP.mul(d).div(xp[j].mul(numTokens));\n                // If we were to protect the division loss we would have to keep the denominator separate\n                // and divide at the end. However this leads to overflow with large numTokens or/and D.\n                // dP = dP * D * D * D * ... overflow!\n            }\n            prevD = d;\n            d = nA.mul(s).div(A_PRECISION).add(dP.mul(numTokens)).mul(d).div(\n                nA.sub(A_PRECISION).mul(d).div(A_PRECISION).add(\n                    numTokens.add(1).mul(dP)\n                )\n            );\n            if (d.within1(prevD)) {\n                return d;\n            }\n        }\n\n        // Convergence should occur in 4 loops or less. If this is reached, there may be something wrong\n        // with the pool. If this were to occur repeatedly, LPs should withdraw via `removeLiquidity()`\n        // function which does not rely on D.\n        revert(\"D does not converge\");\n    }\n\n    /**\n     * @notice Get D, the StableSwap invariant, based on self Swap struct\n     * @param self Swap struct to read from\n     * @return The invariant, at the precision of the pool\n     */\n    function getD(Swap storage self) internal view returns (uint256) {\n        return getD(_xp(self), _getAPrecise(self));\n    }\n\n    /**\n     * @notice Given a set of balances and precision multipliers, return the\n     * precision-adjusted balances.\n     *\n     * @param balances an array of token balances, in their native precisions.\n     * These should generally correspond with pooled tokens.\n     *\n     * @param precisionMultipliers an array of multipliers, corresponding to\n     * the amounts in the balances array. When multiplied together they\n     * should yield amounts at the pool's precision.\n     *\n     * @return an array of amounts \"scaled\" to the pool's precision\n     */\n    function _xp(\n        uint256[] memory balances,\n        uint256[] memory precisionMultipliers\n    ) internal pure returns (uint256[] memory) {\n        uint256 numTokens = balances.length;\n        require(\n            numTokens == precisionMultipliers.length,\n            \"Balances must match multipliers\"\n        );\n        uint256[] memory xp = new uint256[](numTokens);\n        for (uint256 i = 0; i < numTokens; i++) {\n            xp[i] = balances[i].mul(precisionMultipliers[i]);\n        }\n        return xp;\n    }\n\n    /**\n     * @notice Return the precision-adjusted balances of all tokens in the pool\n     * @param self Swap struct to read from\n     * @param balances array of balances to scale\n     * @return balances array \"scaled\" to the pool's precision, allowing\n     * them to be more easily compared.\n     */\n    function _xp(Swap storage self, uint256[] memory balances)\n        internal\n        view\n        returns (uint256[] memory)\n    {\n        return _xp(balances, self.tokenPrecisionMultipliers);\n    }\n\n    /**\n     * @notice Return the precision-adjusted balances of all tokens in the pool\n     * @param self Swap struct to read from\n     * @return the pool balances \"scaled\" to the pool's precision, allowing\n     * them to be more easily compared.\n     */\n    function _xp(Swap storage self) internal view returns (uint256[] memory) {\n        return _xp(self.balances, self.tokenPrecisionMultipliers);\n    }\n\n    /**\n     * @notice Get the virtual price, to help calculate profit\n     * @param self Swap struct to read from\n     * @return the virtual price, scaled to precision of POOL_PRECISION_DECIMALS\n     */\n    function getVirtualPrice(Swap storage self)\n        external\n        view\n        returns (uint256)\n    {\n        uint256 d = getD(_xp(self), _getAPrecise(self));\n        uint256 supply = self.lpToken.totalSupply();\n        if (supply > 0) {\n            return\n                d.mul(10**uint256(ERC20(self.lpToken).decimals())).div(supply);\n        }\n        return 0;\n    }\n\n    /**\n     * @notice Calculate the new balances of the tokens given the indexes of the token\n     * that is swapped from (FROM) and the token that is swapped to (TO).\n     * This function is used as a helper function to calculate how much TO token\n     * the user should receive on swap.\n     *\n     * @param self Swap struct to read from\n     * @param tokenIndexFrom index of FROM token\n     * @param tokenIndexTo index of TO token\n     * @param x the new total amount of FROM token\n     * @param xp balances of the tokens in the pool\n     * @return the amount of TO token that should remain in the pool\n     */\n    function getY(\n        Swap storage self,\n        uint8 tokenIndexFrom,\n        uint8 tokenIndexTo,\n        uint256 x,\n        uint256[] memory xp\n    ) internal view returns (uint256) {\n        uint256 numTokens = self.pooledTokens.length;\n        require(\n            tokenIndexFrom != tokenIndexTo,\n            \"Can't compare token to itself\"\n        );\n        require(\n            tokenIndexFrom < numTokens && tokenIndexTo < numTokens,\n            \"Tokens must be in pool\"\n        );\n\n        uint256 a = _getAPrecise(self);\n        uint256 d = getD(xp, a);\n        uint256 c = d;\n        uint256 s;\n        uint256 nA = numTokens.mul(a);\n\n        uint256 _x;\n        for (uint256 i = 0; i < numTokens; i++) {\n            if (i == tokenIndexFrom) {\n                _x = x;\n            } else if (i != tokenIndexTo) {\n                _x = xp[i];\n            } else {\n                continue;\n            }\n            s = s.add(_x);\n            c = c.mul(d).div(_x.mul(numTokens));\n            // If we were to protect the division loss we would have to keep the denominator separate\n            // and divide at the end. However this leads to overflow with large numTokens or/and D.\n            // c = c * D * D * D * ... overflow!\n        }\n        c = c.mul(d).mul(A_PRECISION).div(nA.mul(numTokens));\n        uint256 b = s.add(d.mul(A_PRECISION).div(nA));\n        uint256 yPrev;\n        uint256 y = d;\n\n        // iterative approximation\n        for (uint256 i = 0; i < MAX_LOOP_LIMIT; i++) {\n            yPrev = y;\n            y = y.mul(y).add(c).div(y.mul(2).add(b).sub(d));\n            if (y.within1(yPrev)) {\n                return y;\n            }\n        }\n        revert(\"Approximation did not converge\");\n    }\n\n    /**\n     * @notice Externally calculates a swap between two tokens.\n     * @param self Swap struct to read from\n     * @param tokenIndexFrom the token to sell\n     * @param tokenIndexTo the token to buy\n     * @param dx the number of tokens to sell. If the token charges a fee on transfers,\n     * use the amount that gets transferred after the fee.\n     * @return dy the number of tokens the user will get\n     */\n    function calculateSwap(\n        Swap storage self,\n        uint8 tokenIndexFrom,\n        uint8 tokenIndexTo,\n        uint256 dx\n    ) external view returns (uint256 dy) {\n        (dy, ) = _calculateSwap(self, tokenIndexFrom, tokenIndexTo, dx);\n    }\n\n    /**\n     * @notice Internally calculates a swap between two tokens.\n     *\n     * @dev The caller is expected to transfer the actual amounts (dx and dy)\n     * using the token contracts.\n     *\n     * @param self Swap struct to read from\n     * @param tokenIndexFrom the token to sell\n     * @param tokenIndexTo the token to buy\n     * @param dx the number of tokens to sell. If the token charges a fee on transfers,\n     * use the amount that gets transferred after the fee.\n     * @return dy the number of tokens the user will get\n     * @return dyFee the associated fee\n     */\n    function _calculateSwap(\n        Swap storage self,\n        uint8 tokenIndexFrom,\n        uint8 tokenIndexTo,\n        uint256 dx\n    ) internal view returns (uint256 dy, uint256 dyFee) {\n        uint256[] memory xp = _xp(self);\n        require(\n            tokenIndexFrom < xp.length && tokenIndexTo < xp.length,\n            \"Token index out of range\"\n        );\n        uint256 x =\n            dx.mul(self.tokenPrecisionMultipliers[tokenIndexFrom]).add(\n                xp[tokenIndexFrom]\n            );\n        uint256 y = getY(self, tokenIndexFrom, tokenIndexTo, x, xp);\n        dy = xp[tokenIndexTo].sub(y).sub(1);\n        dyFee = dy.mul(self.swapFee).div(FEE_DENOMINATOR);\n        dy = dy.sub(dyFee).div(self.tokenPrecisionMultipliers[tokenIndexTo]);\n    }\n\n    /**\n     * @notice A simple method to calculate amount of each underlying\n     * tokens that is returned upon burning given amount of\n     * LP tokens\n     *\n     * @param account the address that is removing liquidity. required for withdraw fee calculation\n     * @param amount the amount of LP tokens that would to be burned on\n     * withdrawal\n     * @return array of amounts of tokens user will receive\n     */\n    function calculateRemoveLiquidity(\n        Swap storage self,\n        address account,\n        uint256 amount\n    ) external view returns (uint256[] memory) {\n        return _calculateRemoveLiquidity(self, account, amount);\n    }\n\n    function _calculateRemoveLiquidity(\n        Swap storage self,\n        address account,\n        uint256 amount\n    ) internal view returns (uint256[] memory) {\n        uint256 totalSupply = self.lpToken.totalSupply();\n        require(amount <= totalSupply, \"Cannot exceed total supply\");\n\n        uint256 feeAdjustedAmount = amount;\n\n            // No fees for withdrawals!\n            // amount\n            //     .mul(\n            //     FEE_DENOMINATOR.sub(calculateCurrentWithdrawFee(self, account))\n            // )\n            //     .div(FEE_DENOMINATOR);\n\n        uint256[] memory amounts = new uint256[](self.pooledTokens.length);\n\n        for (uint256 i = 0; i < self.pooledTokens.length; i++) {\n            amounts[i] = self.balances[i].mul(feeAdjustedAmount).div(\n                totalSupply\n            );\n        }\n        return amounts;\n    }\n\n    /**\n     * @notice Calculate the fee that is applied when the given user withdraws.\n     * Withdraw fee decays linearly over 4 weeks.\n     * @param user address you want to calculate withdraw fee of\n     * @return current withdraw fee of the user\n     */\n    function calculateCurrentWithdrawFee(Swap storage self, address user)\n        public\n        view\n        returns (uint256)\n    {\n        uint256 endTime = self.depositTimestamp[user].add(4 weeks);\n        if (endTime > block.timestamp) {\n            uint256 timeLeftover = endTime.sub(block.timestamp);\n            return\n                self\n                    .defaultWithdrawFee\n                    .mul(self.withdrawFeeMultiplier[user])\n                    .mul(timeLeftover)\n                    .div(4 weeks)\n                    .div(FEE_DENOMINATOR);\n        }\n        return 0;\n    }\n\n    /**\n     * @notice A simple method to calculate prices from deposits or\n     * withdrawals, excluding fees but including slippage. This is\n     * helpful as an input into the various \"min\" parameters on calls\n     * to fight front-running\n     *\n     * @dev This shouldn't be used outside frontends for user estimates.\n     *\n     * @param self Swap struct to read from\n     * @param account address of the account depositing or withdrawing tokens\n     * @param amounts an array of token amounts to deposit or withdrawal,\n     * corresponding to pooledTokens. The amount should be in each\n     * pooled token's native precision. If a token charges a fee on transfers,\n     * use the amount that gets transferred after the fee.\n     * @param deposit whether this is a deposit or a withdrawal\n     * @return if deposit was true, total amount of lp token that will be minted and if\n     * deposit was false, total amount of lp token that will be burned\n     */\n    function calculateTokenAmount(\n        Swap storage self,\n        address account,\n        uint256[] calldata amounts,\n        bool deposit\n    ) external view returns (uint256) {\n        uint256 numTokens = self.pooledTokens.length;\n        uint256 a = _getAPrecise(self);\n        uint256 d0 = getD(_xp(self, self.balances), a);\n        uint256[] memory balances1 = self.balances;\n        for (uint256 i = 0; i < numTokens; i++) {\n            if (deposit) {\n                balances1[i] = balances1[i].add(amounts[i]);\n            } else {\n                balances1[i] = balances1[i].sub(\n                    amounts[i],\n                    \"Cannot withdraw more than available\"\n                );\n            }\n        }\n        uint256 d1 = getD(_xp(self, balances1), a);\n        uint256 totalSupply = self.lpToken.totalSupply();\n\n        if (deposit) {\n            return d1.sub(d0).mul(totalSupply).div(d0);\n        } else {\n            return\n                d0.sub(d1).mul(totalSupply).div(d0).mul(FEE_DENOMINATOR).div(\n                    FEE_DENOMINATOR.sub(\n                        calculateCurrentWithdrawFee(self, account)\n                    )\n                );\n        }\n    }\n\n    /**\n     * @notice return accumulated amount of admin fees of the token with given index\n     * @param self Swap struct to read from\n     * @param index Index of the pooled token\n     * @return admin balance in the token's precision\n     */\n    function getAdminBalance(Swap storage self, uint256 index)\n        external\n        view\n        returns (uint256)\n    {\n        require(index < self.pooledTokens.length, \"Token index out of range\");\n        return\n            self.pooledTokens[index].balanceOf(address(this)).sub(\n                self.balances[index]\n            );\n    }\n\n    /**\n     * @notice internal helper function to calculate fee per token multiplier used in\n     * swap fee calculations\n     * @param self Swap struct to read from\n     */\n    function _feePerToken(Swap storage self) internal view returns (uint256) {\n        return\n            self.swapFee.mul(self.pooledTokens.length).div(\n                self.pooledTokens.length.sub(1).mul(4)\n            );\n    }\n\n    /*** STATE MODIFYING FUNCTIONS ***/\n\n    /**\n     * @notice swap two tokens in the pool\n     * @param self Swap struct to read from and write to\n     * @param tokenIndexFrom the token the user wants to sell\n     * @param tokenIndexTo the token the user wants to buy\n     * @param dx the amount of tokens the user wants to sell\n     * @param minDy the min amount the user would like to receive, or revert.\n     * @return amount of token user received on swap\n     */\n    function swap(\n        Swap storage self,\n        uint8 tokenIndexFrom,\n        uint8 tokenIndexTo,\n        uint256 dx,\n        uint256 minDy\n    ) external returns (uint256) {\n        require(\n            dx <= self.pooledTokens[tokenIndexFrom].balanceOf(msg.sender),\n            \"Cannot swap more than you own\"\n        );\n\n        // Transfer tokens first to see if a fee was charged on transfer\n        uint256 beforeBalance =\n            self.pooledTokens[tokenIndexFrom].balanceOf(address(this));\n        self.pooledTokens[tokenIndexFrom].safeTransferFrom(\n            msg.sender,\n            address(this),\n            dx\n        );\n\n        // Use the actual transferred amount for AMM math\n        uint256 transferredDx =\n            self.pooledTokens[tokenIndexFrom].balanceOf(address(this)).sub(\n                beforeBalance\n            );\n\n        (uint256 dy, uint256 dyFee) =\n            _calculateSwap(self, tokenIndexFrom, tokenIndexTo, transferredDx);\n        require(dy >= minDy, \"Swap didn't result in min tokens\");\n\n        uint256 dyAdminFee =\n            dyFee.mul(self.adminFee).div(FEE_DENOMINATOR).div(\n                self.tokenPrecisionMultipliers[tokenIndexTo]\n            );\n\n        self.balances[tokenIndexFrom] = self.balances[tokenIndexFrom].add(\n            transferredDx\n        );\n        self.balances[tokenIndexTo] = self.balances[tokenIndexTo].sub(dy).sub(\n            dyAdminFee\n        );\n\n        self.pooledTokens[tokenIndexTo].safeTransfer(msg.sender, dy);\n\n        emit TokenSwap(\n            msg.sender,\n            transferredDx,\n            dy,\n            tokenIndexFrom,\n            tokenIndexTo\n        );\n\n        return dy;\n    }\n\n    /**\n     * @notice Add liquidity to the pool\n     * @param self Swap struct to read from and write to\n     * @param amounts the amounts of each token to add, in their native precision\n     * @param minToMint the minimum LP tokens adding this amount of liquidity\n     * should mint, otherwise revert. Handy for front-running mitigation\n     * @return amount of LP token user received\n     */\n    function addLiquidity(\n        Swap storage self,\n        uint256[] memory amounts,\n        uint256 minToMint\n    ) external returns (uint256) {\n        require(\n            amounts.length == self.pooledTokens.length,\n            \"Amounts must match pooled tokens\"\n        );\n\n        uint256[] memory fees = new uint256[](self.pooledTokens.length);\n        uint256 lpTotalSupply = self.lpToken.totalSupply();\n        // current state\n        AddLiquidityInfo memory v = AddLiquidityInfo(0, 0, 0, 0);\n\n        if (lpTotalSupply != 0) {\n            v.d0 = getD(self);\n        }\n        uint256[] memory newBalances = self.balances;\n\n        for (uint256 i = 0; i < self.pooledTokens.length; i++) {\n            require(\n                lpTotalSupply != 0 || amounts[i] > 0,\n                \"Must supply all tokens in pool\"\n            );\n\n            // Transfer tokens first to see if a fee was charged on transfer\n            if (amounts[i] != 0) {\n                uint256 beforeBalance =\n                    self.pooledTokens[i].balanceOf(address(this));\n                self.pooledTokens[i].safeTransferFrom(\n                    msg.sender,\n                    address(this),\n                    amounts[i]\n                );\n\n                // Update the amounts[] with actual transfer amount\n                amounts[i] = self.pooledTokens[i].balanceOf(address(this)).sub(\n                    beforeBalance\n                );\n            }\n\n            newBalances[i] = self.balances[i].add(amounts[i]);\n        }\n\n        // invariant after change\n        v.preciseA = _getAPrecise(self);\n        v.d1 = getD(_xp(self, newBalances), v.preciseA);\n        require(v.d1 > v.d0, \"D should increase\");\n\n        // updated to reflect fees and calculate the user's LP tokens\n        v.d2 = v.d1;\n        if (lpTotalSupply != 0) {\n            uint256 feePerToken = _feePerToken(self);\n            for (uint256 i = 0; i < self.pooledTokens.length; i++) {\n                uint256 idealBalance = v.d1.mul(self.balances[i]).div(v.d0);\n                fees[i] = feePerToken\n                    .mul(idealBalance.difference(newBalances[i]))\n                    .div(FEE_DENOMINATOR);\n                self.balances[i] = newBalances[i].sub(\n                    fees[i].mul(self.adminFee).div(FEE_DENOMINATOR)\n                );\n                newBalances[i] = newBalances[i].sub(fees[i]);\n            }\n            v.d2 = getD(_xp(self, newBalances), v.preciseA);\n        } else {\n            // the initial depositor doesn't pay fees\n            self.balances = newBalances;\n        }\n\n        uint256 toMint;\n        uint256 toMintFee;\n        uint256 toMintUser;\n        if (lpTotalSupply == 0) {\n            toMint = v.d1;\n        } else {\n            toMint = v.d2.sub(v.d0).mul(lpTotalSupply).div(v.d0);\n        }\n\n        require(toMint >= minToMint, \"Couldn't mint min requested\");\n        // if deposit fee is none, mint full amount\n        if (self.defaultDepositFee == 0) {\n            self.lpToken.mint(msg.sender, toMint);\n        } else {\n            // mint the user's LP tokens minus the deposit fee\n            toMintFee = toMint.mul(self.defaultDepositFee).div(FEE_DENOMINATOR);\n            toMintUser = toMint.sub(toMintFee);\n            self.lpToken.mint(self.devaddr, toMintFee);\n            self.lpToken.mint(msg.sender, toMintUser);\n        }\n       \n        emit AddLiquidity(\n            msg.sender,\n            amounts,\n            fees,\n            v.d1,\n            lpTotalSupply + toMint\n        );\n\n        return toMint;\n    }\n\n    /**\n     * @notice Update the withdraw fee for `user`. If the user is currently\n     * not providing liquidity in the pool, sets to default value. If not, recalculate\n     * the starting withdraw fee based on the last deposit's time & amount relative\n     * to the new deposit.\n     *\n     * @param self Swap struct to read from and write to\n     * @param user address of the user depositing tokens\n     * @param toMint amount of pool tokens to be minted\n     */\n    function updateUserWithdrawFee(\n        Swap storage self,\n        address user,\n        uint256 toMint\n    ) external {\n        _updateUserWithdrawFee(self, user, toMint);\n    }\n\n    function _updateUserWithdrawFee(\n        Swap storage self,\n        address user,\n        uint256 toMint\n    ) internal {\n        // If token is transferred to address 0 (or burned), don't update the fee.\n        if (user == address(0)) {\n            return;\n        }\n        if (self.defaultWithdrawFee == 0) {\n            // If current fee is set to 0%, set multiplier to FEE_DENOMINATOR\n            self.withdrawFeeMultiplier[user] = FEE_DENOMINATOR;\n        } else {\n            // Otherwise, calculate appropriate discount based on last deposit amount\n            uint256 currentFee = calculateCurrentWithdrawFee(self, user);\n            uint256 currentBalance = self.lpToken.balanceOf(user);\n\n            // ((currentBalance * currentFee) + (toMint * defaultWithdrawFee)) * FEE_DENOMINATOR /\n            // ((toMint + currentBalance) * defaultWithdrawFee)\n            self.withdrawFeeMultiplier[user] = currentBalance\n                .mul(currentFee)\n                .add(toMint.mul(self.defaultWithdrawFee))\n                .mul(FEE_DENOMINATOR)\n                .div(toMint.add(currentBalance).mul(self.defaultWithdrawFee));\n        }\n        self.depositTimestamp[user] = block.timestamp;\n    }\n\n    /**\n     * @notice Burn LP tokens to remove liquidity from the pool.\n     * @dev Liquidity can always be removed, even when the pool is paused.\n     * @param self Swap struct to read from and write to\n     * @param amount the amount of LP tokens to burn\n     * @param minAmounts the minimum amounts of each token in the pool\n     * acceptable for this burn. Useful as a front-running mitigation\n     * @return amounts of tokens the user received\n     */\n    function removeLiquidity(\n        Swap storage self,\n        uint256 amount,\n        uint256[] calldata minAmounts\n    ) external returns (uint256[] memory) {\n        require(amount <= self.lpToken.balanceOf(msg.sender), \">LP.balanceOf\");\n        require(\n            minAmounts.length == self.pooledTokens.length,\n            \"minAmounts must match poolTokens\"\n        );\n\n        uint256[] memory amounts =\n            _calculateRemoveLiquidity(self, msg.sender, amount);\n\n        for (uint256 i = 0; i < amounts.length; i++) {\n            require(amounts[i] >= minAmounts[i], \"amounts[i] < minAmounts[i]\");\n            self.balances[i] = self.balances[i].sub(amounts[i]);\n            self.pooledTokens[i].safeTransfer(msg.sender, amounts[i]);\n        }\n\n        self.lpToken.burnFrom(msg.sender, amount);\n\n        emit RemoveLiquidity(msg.sender, amounts, self.lpToken.totalSupply());\n\n        return amounts;\n    }\n\n    /**\n     * @notice Remove liquidity from the pool all in one token.\n     * @param self Swap struct to read from and write to\n     * @param tokenAmount the amount of the lp tokens to burn\n     * @param tokenIndex the index of the token you want to receive\n     * @param minAmount the minimum amount to withdraw, otherwise revert\n     * @return amount chosen token that user received\n     */\n    function removeLiquidityOneToken(\n        Swap storage self,\n        uint256 tokenAmount,\n        uint8 tokenIndex,\n        uint256 minAmount\n    ) external returns (uint256) {\n        uint256 totalSupply = self.lpToken.totalSupply();\n        uint256 numTokens = self.pooledTokens.length;\n        require(\n            tokenAmount <= self.lpToken.balanceOf(msg.sender),\n            \">LP.balanceOf\"\n        );\n        require(tokenIndex < numTokens, \"Token not found\");\n\n        uint256 dyFee;\n        uint256 dy;\n\n        (dy, dyFee) = calculateWithdrawOneToken(\n            self,\n            msg.sender,\n            tokenAmount,\n            tokenIndex\n        );\n\n        require(dy >= minAmount, \"dy < minAmount\");\n\n        self.balances[tokenIndex] = self.balances[tokenIndex].sub(\n            dy.add(dyFee.mul(self.adminFee).div(FEE_DENOMINATOR))\n        );\n        self.lpToken.burnFrom(msg.sender, tokenAmount);\n        self.pooledTokens[tokenIndex].safeTransfer(msg.sender, dy);\n\n        emit RemoveLiquidityOne(\n            msg.sender,\n            tokenAmount,\n            totalSupply,\n            tokenIndex,\n            dy\n        );\n\n        return dy;\n    }\n\n    /**\n     * @notice Remove liquidity from the pool, weighted differently than the\n     * pool's current balances.\n     *\n     * @param self Swap struct to read from and write to\n     * @param amounts how much of each token to withdraw\n     * @param maxBurnAmount the max LP token provider is willing to pay to\n     * remove liquidity. Useful as a front-running mitigation.\n     * @return actual amount of LP tokens burned in the withdrawal\n     */\n    function removeLiquidityImbalance(\n        Swap storage self,\n        uint256[] memory amounts,\n        uint256 maxBurnAmount\n    ) public returns (uint256) {\n        require(\n            amounts.length == self.pooledTokens.length,\n            \"Amounts should match pool tokens\"\n        );\n        require(\n            maxBurnAmount <= self.lpToken.balanceOf(msg.sender) &&\n                maxBurnAmount != 0,\n            \">LP.balanceOf\"\n        );\n\n        RemoveLiquidityImbalanceInfo memory v =\n            RemoveLiquidityImbalanceInfo(0, 0, 0, 0);\n\n        uint256 tokenSupply = self.lpToken.totalSupply();\n        uint256 feePerToken = _feePerToken(self);\n\n        uint256[] memory balances1 = self.balances;\n\n        v.preciseA = _getAPrecise(self);\n        v.d0 = getD(_xp(self), v.preciseA);\n        for (uint256 i = 0; i < self.pooledTokens.length; i++) {\n            balances1[i] = balances1[i].sub(\n                amounts[i],\n                \"Cannot withdraw more than available\"\n            );\n        }\n        v.d1 = getD(_xp(self, balances1), v.preciseA);\n        uint256[] memory fees = new uint256[](self.pooledTokens.length);\n\n        for (uint256 i = 0; i < self.pooledTokens.length; i++) {\n            uint256 idealBalance = v.d1.mul(self.balances[i]).div(v.d0);\n            uint256 difference = idealBalance.difference(balances1[i]);\n            fees[i] = feePerToken.mul(difference).div(FEE_DENOMINATOR);\n            self.balances[i] = balances1[i].sub(\n                fees[i].mul(self.adminFee).div(FEE_DENOMINATOR)\n            );\n            balances1[i] = balances1[i].sub(fees[i]);\n        }\n\n        v.d2 = getD(_xp(self, balances1), v.preciseA);\n\n        uint256 tokenAmount = v.d0.sub(v.d2).mul(tokenSupply).div(v.d0);\n        require(tokenAmount != 0, \"Burnt amount cannot be zero\");\n        tokenAmount = tokenAmount.add(1).mul(FEE_DENOMINATOR).div(\n            FEE_DENOMINATOR.sub(calculateCurrentWithdrawFee(self, msg.sender))\n        );\n\n        require(tokenAmount <= maxBurnAmount, \"tokenAmount > maxBurnAmount\");\n\n        self.lpToken.burnFrom(msg.sender, tokenAmount);\n\n        for (uint256 i = 0; i < self.pooledTokens.length; i++) {\n            self.pooledTokens[i].safeTransfer(msg.sender, amounts[i]);\n        }\n\n        emit RemoveLiquidityImbalance(\n            msg.sender,\n            amounts,\n            fees,\n            v.d1,\n            tokenSupply.sub(tokenAmount)\n        );\n\n        return tokenAmount;\n    }\n\n    /**\n     * @notice withdraw all admin fees to a given address\n     * @param self Swap struct to withdraw fees from\n     * @param to Address to send the fees to\n     */\n    function withdrawAdminFees(Swap storage self, address to) external {\n        for (uint256 i = 0; i < self.pooledTokens.length; i++) {\n            IERC20 token = self.pooledTokens[i];\n            uint256 balance =\n                token.balanceOf(address(this)).sub(self.balances[i]);\n            if (balance != 0) {\n                token.safeTransfer(to, balance);\n            }\n        }\n    }\n\n    /**\n     * @notice Sets the admin fee\n     * @dev adminFee cannot be higher than 100% of the swap fee\n     * @param self Swap struct to update\n     * @param newAdminFee new admin fee to be applied on future transactions\n     */\n    function setAdminFee(Swap storage self, uint256 newAdminFee) external {\n        require(newAdminFee <= MAX_ADMIN_FEE, \"Fee is too high\");\n        self.adminFee = newAdminFee;\n\n        emit NewAdminFee(newAdminFee);\n    }\n\n    /**\n     * @notice update the swap fee\n     * @dev fee cannot be higher than 1% of each swap\n     * @param self Swap struct to update\n     * @param newSwapFee new swap fee to be applied on future transactions\n     */\n    function setSwapFee(Swap storage self, uint256 newSwapFee) external {\n        require(newSwapFee <= MAX_SWAP_FEE, \"Fee is too high\");\n        self.swapFee = newSwapFee;\n\n        emit NewSwapFee(newSwapFee);\n    }\n\n    /**\n     * @notice update the default withdraw fee. This also affects deposits made in the past as well.\n     * @param self Swap struct to update\n     * @param newWithdrawFee new withdraw fee to be applied\n     */\n    function setDefaultWithdrawFee(Swap storage self, uint256 newWithdrawFee)\n        external\n    {\n        require(newWithdrawFee <= MAX_WITHDRAW_FEE, \"Fee is too high\");\n        self.defaultWithdrawFee = newWithdrawFee;\n\n        emit NewWithdrawFee(newWithdrawFee);\n    }\n\n    /**\n     * @notice update the default deposit fee. \n     * @param self Swap struct to update\n     * @param newDepositFee new deposit fee to be applied\n     */\n    function setDefaultDepositFee(Swap storage self, uint256 newDepositFee)\n        external\n    {\n        require(newDepositFee <= MAX_DEPOSIT_FEE, \"Fee is too high\");\n        self.defaultDepositFee = newDepositFee;\n\n        emit NewDepositFee(newDepositFee);\n    }\n\n\n    /**\n     * @notice Start ramping up or down A parameter towards given futureA_ and futureTime_\n     * Checks if the change is too rapid, and commits the new A value only when it falls under\n     * the limit range.\n     * @param self Swap struct to update\n     * @param futureA_ the new A to ramp towards\n     * @param futureTime_ timestamp when the new A should be reached\n     */\n    function rampA(\n        Swap storage self,\n        uint256 futureA_,\n        uint256 futureTime_\n    ) external {\n        require(\n            block.timestamp >= self.initialATime.add(1 days),\n            \"Wait 1 day before starting ramp\"\n        );\n        require(\n            futureTime_ >= block.timestamp.add(MIN_RAMP_TIME),\n            \"Insufficient ramp time\"\n        );\n        require(\n            futureA_ > 0 && futureA_ < MAX_A,\n            \"futureA_ must be > 0 and < MAX_A\"\n        );\n\n        uint256 initialAPrecise = _getAPrecise(self);\n        uint256 futureAPrecise = futureA_.mul(A_PRECISION);\n\n        if (futureAPrecise < initialAPrecise) {\n            require(\n                futureAPrecise.mul(MAX_A_CHANGE) >= initialAPrecise,\n                \"futureA_ is too small\"\n            );\n        } else {\n            require(\n                futureAPrecise <= initialAPrecise.mul(MAX_A_CHANGE),\n                \"futureA_ is too large\"\n            );\n        }\n\n        self.initialA = initialAPrecise;\n        self.futureA = futureAPrecise;\n        self.initialATime = block.timestamp;\n        self.futureATime = futureTime_;\n\n        emit RampA(\n            initialAPrecise,\n            futureAPrecise,\n            block.timestamp,\n            futureTime_\n        );\n    }\n\n    /**\n     * @notice Stops ramping A immediately. Once this function is called, rampA()\n     * cannot be called for another 24 hours\n     * @param self Swap struct to update\n     */\n    function stopRampA(Swap storage self) external {\n        require(self.futureATime > block.timestamp, \"Ramp is already stopped\");\n        uint256 currentA = _getAPrecise(self);\n\n        self.initialA = currentA;\n        self.futureA = currentA;\n        self.initialATime = block.timestamp;\n        self.futureATime = block.timestamp;\n\n        emit StopRampA(currentA, block.timestamp);\n    }\n\n    function setDevAddress(Swap storage self, address _devaddr) public {\n        require(msg.sender == self.devaddr, \"dev: wut?\");\n        require(msg.sender != address(0), \"invalid address\");\n        self.devaddr = _devaddr;\n    }\n}\n\n// File: Swap.sol\n\n/**\n * @title Swap - A StableSwap implementation in solidity.\n * @notice This contract is responsible for custody of closely pegged assets (eg. group of stablecoins)\n * and automatic market making system. Users become an LP (Liquidity Provider) by depositing their tokens\n * in desired ratios for an exchange of the pool token that represents their share of the pool.\n * Users can burn pool tokens and withdraw their share of token(s).\n *\n * Each time a swap between the pooled tokens happens, a set fee incurs which effectively gets\n * distributed to the LPs.\n *\n * In case of emergencies, admin can pause additional deposits, swaps, or single-asset withdraws - which\n * stops the ratio of the tokens in the pool from changing.\n * Users can always withdraw their tokens via multi-asset withdraws.\n *\n * @dev Most of the logic is stored as a library `SwapUtils` for the sake of reducing contract's\n * deployment size.\n */\ncontract Swap is OwnerPausable, ReentrancyGuard {\n    using SafeERC20 for IERC20;\n    using SafeMath for uint256;\n    using MathUtils for uint256;\n    using SwapUtils for SwapUtils.Swap;\n\n    // Struct storing data responsible for automatic market maker functionalities. In order to\n    // access this data, this contract uses SwapUtils library. For more details, see SwapUtils.sol\n    SwapUtils.Swap public swapStorage;\n\n    // Maps token address to an index in the pool. Used to prevent duplicate tokens in the pool.\n    // getTokenIndex function also relies on this mapping to retrieve token index.\n    mapping(address => uint8) private tokenIndexes;\n\n    /*** EVENTS ***/\n\n    // events replicated from SwapUtils to make the ABI easier for dumb\n    // clients\n    event TokenSwap(\n        address indexed buyer,\n        uint256 tokensSold,\n        uint256 tokensBought,\n        uint128 soldId,\n        uint128 boughtId\n    );\n    event AddLiquidity(\n        address indexed provider,\n        uint256[] tokenAmounts,\n        uint256[] fees,\n        uint256 invariant,\n        uint256 lpTokenSupply\n    );\n    event RemoveLiquidity(\n        address indexed provider,\n        uint256[] tokenAmounts,\n        uint256 lpTokenSupply\n    );\n    event RemoveLiquidityOne(\n        address indexed provider,\n        uint256 lpTokenAmount,\n        uint256 lpTokenSupply,\n        uint256 boughtId,\n        uint256 tokensBought\n    );\n    event RemoveLiquidityImbalance(\n        address indexed provider,\n        uint256[] tokenAmounts,\n        uint256[] fees,\n        uint256 invariant,\n        uint256 lpTokenSupply\n    );\n    event NewAdminFee(uint256 newAdminFee);\n    event NewSwapFee(uint256 newSwapFee);\n    event NewDepositFee(uint256 newDepositFee);\n    event NewWithdrawFee(uint256 newWithdrawFee);\n    event RampA(\n        uint256 oldA,\n        uint256 newA,\n        uint256 initialTime,\n        uint256 futureTime\n    );\n    event StopRampA(uint256 currentA, uint256 time);\n\n    /**\n     * @notice Deploys this Swap contract with given parameters as default\n     * values. This will also deploy a LPToken that represents users\n     * LP position. The owner of LPToken will be this contract - which means\n     * only this contract is allowed to mint new tokens.\n     *\n     * @param _pooledTokens an array of ERC20s this pool will accept\n     * @param decimals the decimals to use for each pooled token,\n     * eg 8 for WBTC. Cannot be larger than POOL_PRECISION_DECIMALS\n     * @param lpTokenName the long-form name of the token to be deployed\n     * @param lpTokenSymbol the short symbol for the token to be deployed\n     * @param _a the amplification coefficient * n * (n - 1). See the\n     * StableSwap paper for details\n     * @param _fee default swap fee to be initialized with\n     * @param _adminFee default adminFee to be initialized with\n     * @param _depositFee default depositFee to be initialized with\n     * @param _withdrawFee default withdrawFee to be initialized with\n     * @param _devaddr default _devaddr to be initialized with\n     */\n    constructor(\n        IERC20[] memory _pooledTokens,\n        uint8[] memory decimals,\n        string memory lpTokenName,\n        string memory lpTokenSymbol,\n        uint256 _a,\n        uint256 _fee,\n        uint256 _adminFee,\n        uint256 _depositFee,\n        uint256 _withdrawFee,\n        address _devaddr\n    ) public OwnerPausable() ReentrancyGuard() {\n        // Check _pooledTokens and precisions parameter\n        require(_pooledTokens.length > 1, \"_pooledTokens.length <= 1\");\n        require(_pooledTokens.length <= 32, \"_pooledTokens.length > 32\");\n        require(\n            _pooledTokens.length == decimals.length,\n            \"_pooledTokens decimals mismatch\"\n        );\n\n        uint256[] memory precisionMultipliers = new uint256[](decimals.length);\n\n        for (uint8 i = 0; i < _pooledTokens.length; i++) {\n            if (i > 0) {\n                // Check if index is already used. Check if 0th element is a duplicate.\n                require(\n                    tokenIndexes[address(_pooledTokens[i])] == 0 &&\n                        _pooledTokens[0] != _pooledTokens[i],\n                    \"Duplicate tokens\"\n                );\n            }\n            require(\n                address(_pooledTokens[i]) != address(0),\n                \"The 0 address isn't an ERC-20\"\n            );\n            require(\n                decimals[i] <= SwapUtils.POOL_PRECISION_DECIMALS,\n                \"Token decimals exceeds max\"\n            );\n            precisionMultipliers[i] =\n                10 **\n                    uint256(SwapUtils.POOL_PRECISION_DECIMALS).sub(\n                        uint256(decimals[i])\n                    );\n            tokenIndexes[address(_pooledTokens[i])] = i;\n        }\n\n        // Check _a, _fee, _adminFee, _depositFee, _withdrawFee\n        require(_a < SwapUtils.MAX_A, \"_a exceeds maximum\");\n        require(_fee < SwapUtils.MAX_SWAP_FEE, \"_fee exceeds maximum\");\n        require(\n            _adminFee < SwapUtils.MAX_ADMIN_FEE,\n            \"_adminFee exceeds maximum\"\n        );\n        require(\n            _withdrawFee < SwapUtils.MAX_WITHDRAW_FEE,\n            \"_withdrawFee exceeds maximum\"\n        );\n        require(\n            _depositFee < SwapUtils.MAX_DEPOSIT_FEE,\n            \"_depositFee exceeds maximum\"\n        );\n\n        // Initialize swapStorage struct\n        swapStorage.lpToken = new LPToken(\n            lpTokenName,\n            lpTokenSymbol,\n            SwapUtils.POOL_PRECISION_DECIMALS\n        );\n        swapStorage.pooledTokens = _pooledTokens;\n        swapStorage.tokenPrecisionMultipliers = precisionMultipliers;\n        swapStorage.balances = new uint256[](_pooledTokens.length);\n        swapStorage.initialA = _a.mul(SwapUtils.A_PRECISION);\n        swapStorage.futureA = _a.mul(SwapUtils.A_PRECISION);\n        swapStorage.initialATime = 0;\n        swapStorage.futureATime = 0;\n        swapStorage.swapFee = _fee;\n        swapStorage.adminFee = _adminFee;\n        swapStorage.defaultDepositFee = _depositFee;\n        swapStorage.defaultWithdrawFee = _withdrawFee;\n        swapStorage.devaddr = _devaddr;\n\n    }\n\n    /*** MODIFIERS ***/\n\n    /**\n     * @notice Modifier to check deadline against current timestamp\n     * @param deadline latest timestamp to accept this transaction\n     */\n    modifier deadlineCheck(uint256 deadline) {\n        require(block.timestamp <= deadline, \"Deadline not met\");\n        _;\n    }\n\n    /*** VIEW FUNCTIONS ***/\n\n    /**\n     * @notice Return A, the amplification coefficient * n * (n - 1)\n     * @dev See the StableSwap paper for details\n     * @return A parameter\n     */\n    function getA() external view returns (uint256) {\n        return swapStorage.getA();\n    }\n\n    /**\n     * @notice Return A in its raw precision form\n     * @dev See the StableSwap paper for details\n     * @return A parameter in its raw precision form\n     */\n    function getAPrecise() external view returns (uint256) {\n        return swapStorage.getAPrecise();\n    }\n\n    /**\n     * @notice Return address of the pooled token at given index. Reverts if tokenIndex is out of range.\n     * @param index the index of the token\n     * @return address of the token at given index\n     */\n    function getToken(uint8 index) public view returns (IERC20) {\n        require(index < swapStorage.pooledTokens.length, \"Out of range\");\n        return swapStorage.pooledTokens[index];\n    }\n\n    /**\n     * @notice Return the index of the given token address. Reverts if no matching\n     * token is found.\n     * @param tokenAddress address of the token\n     * @return the index of the given token address\n     */\n    function getTokenIndex(address tokenAddress) external view returns (uint8) {\n        uint8 index = tokenIndexes[tokenAddress];\n        require(\n            address(getToken(index)) == tokenAddress,\n            \"Token does not exist\"\n        );\n        return index;\n    }\n\n    /**\n     * @notice Return timestamp of last deposit of given address\n     * @return timestamp of the last deposit made by the given address\n     */\n    function getDepositTimestamp(address user) external view returns (uint256) {\n        return swapStorage.getDepositTimestamp(user);\n    }\n\n    /**\n     * @notice Return current balance of the pooled token at given index\n     * @param index the index of the token\n     * @return current balance of the pooled token at given index with token's native precision\n     */\n    function getTokenBalance(uint8 index) external view returns (uint256) {\n        require(index < swapStorage.pooledTokens.length, \"Index out of range\");\n        return swapStorage.balances[index];\n    }\n\n    /**\n     * @notice Return balances of pooled tokens\n     * @return current balances of all tokens in pool\n     */\n    function getBalances() external view returns (uint256[] memory) {\n        return swapStorage.balances;\n    }\n\n    /**\n        @notice Returns the swap fee\n        @return current swap fee\n     */\n     function getSwapFee() external view returns (uint256) {\n         return swapStorage.swapFee;\n     }\n\n    /**\n        @notice Returns address of lp token\n        @return address of lp token\n     */\n     function getLpToken() external view returns (address) {\n         return address(swapStorage.lpToken);\n     }\n\n    /**\n     * @notice Get the virtual price, to help calculate profit\n     * @return the virtual price, scaled to the POOL_PRECISION_DECIMALS\n     */\n    function getVirtualPrice() external view returns (uint256) {\n        return swapStorage.getVirtualPrice();\n    }\n\n    /**\n     * @notice Calculate amount of tokens you receive on swap\n     * @param tokenIndexFrom the token the user wants to sell\n     * @param tokenIndexTo the token the user wants to buy\n     * @param dx the amount of tokens the user wants to sell. If the token charges\n     * a fee on transfers, use the amount that gets transferred after the fee.\n     * @return amount of tokens the user will receive\n     */\n    function calculateSwap(\n        uint8 tokenIndexFrom,\n        uint8 tokenIndexTo,\n        uint256 dx\n    ) external view returns (uint256) {\n        return swapStorage.calculateSwap(tokenIndexFrom, tokenIndexTo, dx);\n    }\n\n    /**\n     * @notice A simple method to calculate prices from deposits or\n     * withdrawals, excluding fees but including slippage. This is\n     * helpful as an input into the various \"min\" parameters on calls\n     * to fight front-running\n     *\n     * @dev This shouldn't be used outside frontends for user estimates.\n     *\n     * @param account address that is depositing or withdrawing tokens\n     * @param amounts an array of token amounts to deposit or withdrawal,\n     * corresponding to pooledTokens. The amount should be in each\n     * pooled token's native precision. If a token charges a fee on transfers,\n     * use the amount that gets transferred after the fee.\n     * @param deposit whether this is a deposit or a withdrawal\n     * @return token amount the user will receive\n     */\n    function calculateTokenAmount(\n        address account,\n        uint256[] calldata amounts,\n        bool deposit\n    ) external view returns (uint256) {\n        return swapStorage.calculateTokenAmount(account, amounts, deposit);\n    }\n\n    /**\n     * @notice A simple method to calculate amount of each underlying\n     * tokens that is returned upon burning given amount of LP tokens\n     * @param account the address that is withdrawing tokens\n     * @param amount the amount of LP tokens that would be burned on withdrawal\n     * @return array of token balances that the user will receive\n     */\n    function calculateRemoveLiquidity(address account, uint256 amount)\n        external\n        view\n        returns (uint256[] memory)\n    {\n        return swapStorage.calculateRemoveLiquidity(account, amount);\n    }\n\n    /**\n     * @notice Calculate the amount of underlying token available to withdraw\n     * when withdrawing via only single token\n     * @param account the address that is withdrawing tokens\n     * @param tokenAmount the amount of LP token to burn\n     * @param tokenIndex index of which token will be withdrawn\n     * @return availableTokenAmount calculated amount of underlying token\n     * available to withdraw\n     */\n    function calculateRemoveLiquidityOneToken(\n        address account,\n        uint256 tokenAmount,\n        uint8 tokenIndex\n    ) external view returns (uint256 availableTokenAmount) {\n        (availableTokenAmount, ) = swapStorage.calculateWithdrawOneToken(\n            account,\n            tokenAmount,\n            tokenIndex\n        );\n    }\n\n    /**\n     * @notice Calculate the fee that is applied when the given user withdraws. The withdraw fee\n     * decays linearly over period of 4 weeks. For example, depositing and withdrawing right away\n     * will charge you the full amount of withdraw fee. But withdrawing after 4 weeks will charge you\n     * no additional fees.\n     * @dev returned value should be divided by FEE_DENOMINATOR to convert to correct decimals\n     * @param user address you want to calculate withdraw fee of\n     * @return current withdraw fee of the user\n     */\n    function calculateCurrentWithdrawFee(address user)\n        external\n        view\n        returns (uint256)\n    {\n        return swapStorage.calculateCurrentWithdrawFee(user);\n    }\n\n    /**\n     * @notice This function reads the accumulated amount of admin fees of the token with given index\n     * @param index Index of the pooled token\n     * @return admin's token balance in the token's precision\n     */\n    function getAdminBalance(uint256 index) external view returns (uint256) {\n        return swapStorage.getAdminBalance(index);\n    }\n\n    /*** STATE MODIFYING FUNCTIONS ***/\n\n    /**\n     * @notice Swap two tokens using this pool\n     * @param tokenIndexFrom the token the user wants to swap from\n     * @param tokenIndexTo the token the user wants to swap to\n     * @param dx the amount of tokens the user wants to swap from\n     * @param minDy the min amount the user would like to receive, or revert.\n     * @param deadline latest timestamp to accept this transaction\n     */\n    function swap(\n        uint8 tokenIndexFrom,\n        uint8 tokenIndexTo,\n        uint256 dx,\n        uint256 minDy,\n        uint256 deadline\n    )\n        external\n        nonReentrant\n        whenNotPaused\n        deadlineCheck(deadline)\n        returns (uint256)\n    {\n        return swapStorage.swap(tokenIndexFrom, tokenIndexTo, dx, minDy);\n    }\n\n    /**\n     * @notice Add liquidity to the pool with given amounts\n     * @param amounts the amounts of each token to add, in their native precision\n     * @param minToMint the minimum LP tokens adding this amount of liquidity\n     * should mint, otherwise revert. Handy for front-running mitigation\n     * @param deadline latest timestamp to accept this transaction\n     * @return amount of LP token user minted and received\n     */\n    function addLiquidity(\n        uint256[] calldata amounts,\n        uint256 minToMint,\n        uint256 deadline\n    )\n        external\n        nonReentrant\n        whenNotPaused\n        deadlineCheck(deadline)\n        returns (uint256)\n    {\n        return swapStorage.addLiquidity(amounts, minToMint);\n    }\n\n    /**\n     * @notice Burn LP tokens to remove liquidity from the pool. Withdraw fee that decays linearly\n     * over period of 4 weeks since last deposit will apply.\n     * @dev Liquidity can always be removed, even when the pool is paused.\n     * @param amount the amount of LP tokens to burn\n     * @param minAmounts the minimum amounts of each token in the pool\n     *        acceptable for this burn. Useful as a front-running mitigation\n     * @param deadline latest timestamp to accept this transaction\n     * @return amounts of tokens user received\n     */\n    function removeLiquidity(\n        uint256 amount,\n        uint256[] calldata minAmounts,\n        uint256 deadline\n    ) external nonReentrant deadlineCheck(deadline) returns (uint256[] memory) {\n        return swapStorage.removeLiquidity(amount, minAmounts);\n    }\n\n    /**\n     * @notice Remove liquidity from the pool all in one token. Withdraw fee that decays linearly\n     * over period of 4 weeks since last deposit will apply.\n     * @param tokenAmount the amount of the token you want to receive\n     * @param tokenIndex the index of the token you want to receive\n     * @param minAmount the minimum amount to withdraw, otherwise revert\n     * @param deadline latest timestamp to accept this transaction\n     * @return amount of chosen token user received\n     */\n    function removeLiquidityOneToken(\n        uint256 tokenAmount,\n        uint8 tokenIndex,\n        uint256 minAmount,\n        uint256 deadline\n    )\n        external\n        nonReentrant\n        whenNotPaused\n        deadlineCheck(deadline)\n        returns (uint256)\n    {\n        return\n            swapStorage.removeLiquidityOneToken(\n                tokenAmount,\n                tokenIndex,\n                minAmount\n            );\n    }\n\n    /**\n     * @notice Remove liquidity from the pool, weighted differently than the\n     * pool's current balances. Withdraw fee that decays linearly\n     * over period of 4 weeks since last deposit will apply.\n     * @param amounts how much of each token to withdraw\n     * @param maxBurnAmount the max LP token provider is willing to pay to\n     * remove liquidity. Useful as a front-running mitigation.\n     * @param deadline latest timestamp to accept this transaction\n     * @return amount of LP tokens burned\n     */\n    function removeLiquidityImbalance(\n        uint256[] calldata amounts,\n        uint256 maxBurnAmount,\n        uint256 deadline\n    )\n        external\n        nonReentrant\n        whenNotPaused\n        deadlineCheck(deadline)\n        returns (uint256)\n    {\n        return swapStorage.removeLiquidityImbalance(amounts, maxBurnAmount);\n    }\n\n    /*** ADMIN FUNCTIONS ***/\n\n    /**\n     * @notice Updates the user withdraw fee. This function can only be called by\n     * the pool token. Should be used to update the withdraw fee on transfer of pool tokens.\n     * Transferring your pool token will reset the 4 weeks period. If the recipient is already\n     * holding some pool tokens, the withdraw fee will be discounted in respective amounts.\n     * @param recipient address of the recipient of pool token\n     * @param transferAmount amount of pool token to transfer\n     */\n    function updateUserWithdrawFee(address recipient, uint256 transferAmount)\n        external\n    {\n        require(\n            msg.sender == address(swapStorage.lpToken),\n            \"Only callable by pool token\"\n        );\n        swapStorage.updateUserWithdrawFee(recipient, transferAmount);\n    }\n\n    /**\n     * @notice Withdraw all admin fees to the contract owner\n     */\n    function withdrawAdminFees() external onlyOwner {\n        swapStorage.withdrawAdminFees(owner());\n    }\n\n    /**\n     * @notice Update the admin fee. Admin fee takes portion of the swap fee.\n     * @param newAdminFee new admin fee to be applied on future transactions\n     */\n    function setAdminFee(uint256 newAdminFee) external onlyOwner {\n        swapStorage.setAdminFee(newAdminFee);\n    }\n\n    /**\n     * @notice Update the swap fee to be applied on swaps\n     * @param newSwapFee new swap fee to be applied on future transactions\n     */\n    function setSwapFee(uint256 newSwapFee) external onlyOwner {\n        swapStorage.setSwapFee(newSwapFee);\n    }\n\n        /**\n     * @notice Update the deposit fee. \n     * @param newDepositFee new deposit fee to be applied on future deposits\n     */\n    function setDefaultDepositFee(uint256 newDepositFee) external onlyOwner {\n        swapStorage.setDefaultDepositFee(newDepositFee);\n    }\n\n    /**\n     * @notice Update the withdraw fee. This fee decays linearly over 4 weeks since\n     * user's last deposit.\n     * @param newWithdrawFee new withdraw fee to be applied on future deposits\n     */\n    function setDefaultWithdrawFee(uint256 newWithdrawFee) external onlyOwner {\n        swapStorage.setDefaultWithdrawFee(newWithdrawFee);\n    }\n\n    /**\n     * @notice Start ramping up or down A parameter towards given futureA and futureTime\n     * Checks if the change is too rapid, and commits the new A value only when it falls under\n     * the limit range.\n     * @param futureA the new A to ramp towards\n     * @param futureTime timestamp when the new A should be reached\n     */\n    function rampA(uint256 futureA, uint256 futureTime) external onlyOwner {\n        swapStorage.rampA(futureA, futureTime);\n    }\n\n    /**\n     * @notice Stop ramping A immediately. Reverts if ramp A is already stopped.\n     */\n    function stopRampA() external onlyOwner {\n        swapStorage.stopRampA();\n    }\n\n        // Update dev address by the previous dev.\n    function setDevAddress(address _devaddr) external onlyOwner {\n        swapStorage.setDevAddress(_devaddr);\n    }\n}\n", "contract_name": "Swap", "compiler_version": "0.6.12+commit.27d51765", "optimizer_enabled": true, "optimizer_runs": 200, "license_identifier": "MIT", "bytecode_len": 36224}