ETH Price: $1,979.77 (+0.66%)

Transaction Decoder

Block:
23271167 at Sep-01-2025 10:07:11 PM +UTC
Transaction Fee:
0.000157309779096296 ETH $0.31
Gas Used:
101,533 Gas / 1.549346312 Gwei

Emitted Events:

272 IBITToken.Transfer( from=[Receiver] Vault, to=[Sender] 0x016c8a50ee563aadaa294eae9cd6cd0d5b08c006, value=785650000000000000000 )
273 Vault.Withdrawn( nonce=16793, account=[Sender] 0x016c8a50ee563aadaa294eae9cd6cd0d5b08c006, token=IBITToken, amount=785650000000000000000, timestamp=1756764431 )

Account State Difference:

  Address   Before After State Difference Code
0x016C8a50...D5B08c006
0.002002319924590358 Eth
Nonce: 59
0.001845010145494062 Eth
Nonce: 60
0.000157309779096296
(Titan Builder)
34.273958041970553716 Eth34.273985293402675065 Eth0.000027251432121349
0x6fa651bD...BE689c96D
0xDE78c0f6...0A54ED948

Execution Trace

Vault.withdraw( _nonce=16793, _token=0xDE78c0f6717332e743d1b8794c346850A54ED948, _account=0x016C8a50EE563AAdAA294EaE9cd6cD0D5B08c006, _amount=785650000000000000000, _signature=0x5FA52D2C5EFFA19AA53524A080B2EE090F5B38B614792311B3BF6331F31EDC5179ACCE5F1305BEC1EF623148B597EEDD29DC1C33A0569677DDF30020373811B11C )
  • Null: 0x000...001.d3872163( )
  • IBITToken.transfer( recipient=0x016C8a50EE563AAdAA294EaE9cd6cD0D5B08c006, amount=785650000000000000000 ) => ( True )
    File 1 of 2: Vault
    // File: @openzeppelin/contracts/utils/Context.sol
    
    
    // OpenZeppelin Contracts (last updated v5.0.1) (utils/Context.sol)
    
    pragma solidity ^0.8.20;
    
    /**
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context {
        function _msgSender() internal view virtual returns (address) {
            return msg.sender;
        }
    
        function _msgData() internal view virtual returns (bytes calldata) {
            return msg.data;
        }
    
        function _contextSuffixLength() internal view virtual returns (uint256) {
            return 0;
        }
    }
    
    // File: @openzeppelin/contracts/access/Ownable.sol
    
    
    // OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)
    
    pragma solidity ^0.8.20;
    
    
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * The initial owner is set to the address provided by the deployer. This can
     * later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
    
        /**
         * @dev The caller account is not authorized to perform an operation.
         */
        error OwnableUnauthorizedAccount(address account);
    
        /**
         * @dev The owner is not a valid owner account. (eg. `address(0)`)
         */
        error OwnableInvalidOwner(address owner);
    
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    
        /**
         * @dev Initializes the contract setting the address provided by the deployer as the initial owner.
         */
        constructor(address initialOwner) {
            if (initialOwner == address(0)) {
                revert OwnableInvalidOwner(address(0));
            }
            _transferOwnership(initialOwner);
        }
    
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            _checkOwner();
            _;
        }
    
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
    
        /**
         * @dev Throws if the sender is not the owner.
         */
        function _checkOwner() internal view virtual {
            if (owner() != _msgSender()) {
                revert OwnableUnauthorizedAccount(_msgSender());
            }
        }
    
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby disabling any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            _transferOwnership(address(0));
        }
    
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            if (newOwner == address(0)) {
                revert OwnableInvalidOwner(address(0));
            }
            _transferOwnership(newOwner);
        }
    
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Internal function without access restriction.
         */
        function _transferOwnership(address newOwner) internal virtual {
            address oldOwner = _owner;
            _owner = newOwner;
            emit OwnershipTransferred(oldOwner, newOwner);
        }
    }
    
    // File: @openzeppelin/contracts/token/ERC20/IERC20.sol
    
    
    // OpenZeppelin Contracts (last updated v5.1.0) (token/ERC20/IERC20.sol)
    
    pragma solidity ^0.8.20;
    
    /**
     * @dev Interface of the ERC-20 standard as defined in the ERC.
     */
    interface IERC20 {
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
    
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
    
        /**
         * @dev Returns the value of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
    
        /**
         * @dev Returns the value of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
    
        /**
         * @dev Moves a `value` amount of tokens from the caller's account to `to`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address to, uint256 value) external returns (bool);
    
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
    
        /**
         * @dev Sets a `value` amount of tokens as the allowance of `spender` over the
         * caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 value) external returns (bool);
    
        /**
         * @dev Moves a `value` amount of tokens from `from` to `to` using the
         * allowance mechanism. `value` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(address from, address to, uint256 value) external returns (bool);
    }
    
    // File: @openzeppelin/contracts/interfaces/IERC20.sol
    
    
    // OpenZeppelin Contracts (last updated v5.0.0) (interfaces/IERC20.sol)
    
    pragma solidity ^0.8.20;
    
    
    // File: @openzeppelin/contracts/utils/introspection/IERC165.sol
    
    
    // OpenZeppelin Contracts (last updated v5.1.0) (utils/introspection/IERC165.sol)
    
    pragma solidity ^0.8.20;
    
    /**
     * @dev Interface of the ERC-165 standard, as defined in the
     * https://eips.ethereum.org/EIPS/eip-165[ERC].
     *
     * Implementers can declare support of contract interfaces, which can then be
     * queried by others ({ERC165Checker}).
     *
     * For an implementation, see {ERC165}.
     */
    interface IERC165 {
        /**
         * @dev Returns true if this contract implements the interface defined by
         * `interfaceId`. See the corresponding
         * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[ERC section]
         * to learn more about how these ids are created.
         *
         * This function call must use less than 30 000 gas.
         */
        function supportsInterface(bytes4 interfaceId) external view returns (bool);
    }
    
    // File: @openzeppelin/contracts/interfaces/IERC165.sol
    
    
    // OpenZeppelin Contracts (last updated v5.0.0) (interfaces/IERC165.sol)
    
    pragma solidity ^0.8.20;
    
    
    // File: @openzeppelin/contracts/interfaces/IERC1363.sol
    
    
    // OpenZeppelin Contracts (last updated v5.1.0) (interfaces/IERC1363.sol)
    
    pragma solidity ^0.8.20;
    
    
    
    /**
     * @title IERC1363
     * @dev Interface of the ERC-1363 standard as defined in the https://eips.ethereum.org/EIPS/eip-1363[ERC-1363].
     *
     * Defines an extension interface for ERC-20 tokens that supports executing code on a recipient contract
     * after `transfer` or `transferFrom`, or code on a spender contract after `approve`, in a single transaction.
     */
    interface IERC1363 is IERC20, IERC165 {
        /*
         * Note: the ERC-165 identifier for this interface is 0xb0202a11.
         * 0xb0202a11 ===
         *   bytes4(keccak256('transferAndCall(address,uint256)')) ^
         *   bytes4(keccak256('transferAndCall(address,uint256,bytes)')) ^
         *   bytes4(keccak256('transferFromAndCall(address,address,uint256)')) ^
         *   bytes4(keccak256('transferFromAndCall(address,address,uint256,bytes)')) ^
         *   bytes4(keccak256('approveAndCall(address,uint256)')) ^
         *   bytes4(keccak256('approveAndCall(address,uint256,bytes)'))
         */
    
        /**
         * @dev Moves a `value` amount of tokens from the caller's account to `to`
         * and then calls {IERC1363Receiver-onTransferReceived} on `to`.
         * @param to The address which you want to transfer to.
         * @param value The amount of tokens to be transferred.
         * @return A boolean value indicating whether the operation succeeded unless throwing.
         */
        function transferAndCall(address to, uint256 value) external returns (bool);
    
        /**
         * @dev Moves a `value` amount of tokens from the caller's account to `to`
         * and then calls {IERC1363Receiver-onTransferReceived} on `to`.
         * @param to The address which you want to transfer to.
         * @param value The amount of tokens to be transferred.
         * @param data Additional data with no specified format, sent in call to `to`.
         * @return A boolean value indicating whether the operation succeeded unless throwing.
         */
        function transferAndCall(address to, uint256 value, bytes calldata data) external returns (bool);
    
        /**
         * @dev Moves a `value` amount of tokens from `from` to `to` using the allowance mechanism
         * and then calls {IERC1363Receiver-onTransferReceived} on `to`.
         * @param from The address which you want to send tokens from.
         * @param to The address which you want to transfer to.
         * @param value The amount of tokens to be transferred.
         * @return A boolean value indicating whether the operation succeeded unless throwing.
         */
        function transferFromAndCall(address from, address to, uint256 value) external returns (bool);
    
        /**
         * @dev Moves a `value` amount of tokens from `from` to `to` using the allowance mechanism
         * and then calls {IERC1363Receiver-onTransferReceived} on `to`.
         * @param from The address which you want to send tokens from.
         * @param to The address which you want to transfer to.
         * @param value The amount of tokens to be transferred.
         * @param data Additional data with no specified format, sent in call to `to`.
         * @return A boolean value indicating whether the operation succeeded unless throwing.
         */
        function transferFromAndCall(address from, address to, uint256 value, bytes calldata data) external returns (bool);
    
        /**
         * @dev Sets a `value` amount of tokens as the allowance of `spender` over the
         * caller's tokens and then calls {IERC1363Spender-onApprovalReceived} on `spender`.
         * @param spender The address which will spend the funds.
         * @param value The amount of tokens to be spent.
         * @return A boolean value indicating whether the operation succeeded unless throwing.
         */
        function approveAndCall(address spender, uint256 value) external returns (bool);
    
        /**
         * @dev Sets a `value` amount of tokens as the allowance of `spender` over the
         * caller's tokens and then calls {IERC1363Spender-onApprovalReceived} on `spender`.
         * @param spender The address which will spend the funds.
         * @param value The amount of tokens to be spent.
         * @param data Additional data with no specified format, sent in call to `spender`.
         * @return A boolean value indicating whether the operation succeeded unless throwing.
         */
        function approveAndCall(address spender, uint256 value, bytes calldata data) external returns (bool);
    }
    
    // File: @openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol
    
    
    // OpenZeppelin Contracts (last updated v5.3.0) (token/ERC20/utils/SafeERC20.sol)
    
    pragma solidity ^0.8.20;
    
    
    
    /**
     * @title SafeERC20
     * @dev Wrappers around ERC-20 operations that throw on failure (when the token
     * contract returns false). Tokens that return no value (and instead revert or
     * throw on failure) are also supported, non-reverting calls are assumed to be
     * successful.
     * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
     * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
     */
    library SafeERC20 {
        /**
         * @dev An operation with an ERC-20 token failed.
         */
        error SafeERC20FailedOperation(address token);
    
        /**
         * @dev Indicates a failed `decreaseAllowance` request.
         */
        error SafeERC20FailedDecreaseAllowance(address spender, uint256 currentAllowance, uint256 requestedDecrease);
    
        /**
         * @dev Transfer `value` amount of `token` from the calling contract to `to`. If `token` returns no value,
         * non-reverting calls are assumed to be successful.
         */
        function safeTransfer(IERC20 token, address to, uint256 value) internal {
            _callOptionalReturn(token, abi.encodeCall(token.transfer, (to, value)));
        }
    
        /**
         * @dev Transfer `value` amount of `token` from `from` to `to`, spending the approval given by `from` to the
         * calling contract. If `token` returns no value, non-reverting calls are assumed to be successful.
         */
        function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
            _callOptionalReturn(token, abi.encodeCall(token.transferFrom, (from, to, value)));
        }
    
        /**
         * @dev Variant of {safeTransfer} that returns a bool instead of reverting if the operation is not successful.
         */
        function trySafeTransfer(IERC20 token, address to, uint256 value) internal returns (bool) {
            return _callOptionalReturnBool(token, abi.encodeCall(token.transfer, (to, value)));
        }
    
        /**
         * @dev Variant of {safeTransferFrom} that returns a bool instead of reverting if the operation is not successful.
         */
        function trySafeTransferFrom(IERC20 token, address from, address to, uint256 value) internal returns (bool) {
            return _callOptionalReturnBool(token, abi.encodeCall(token.transferFrom, (from, to, value)));
        }
    
        /**
         * @dev Increase the calling contract's allowance toward `spender` by `value`. If `token` returns no value,
         * non-reverting calls are assumed to be successful.
         *
         * IMPORTANT: If the token implements ERC-7674 (ERC-20 with temporary allowance), and if the "client"
         * smart contract uses ERC-7674 to set temporary allowances, then the "client" smart contract should avoid using
         * this function. Performing a {safeIncreaseAllowance} or {safeDecreaseAllowance} operation on a token contract
         * that has a non-zero temporary allowance (for that particular owner-spender) will result in unexpected behavior.
         */
        function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
            uint256 oldAllowance = token.allowance(address(this), spender);
            forceApprove(token, spender, oldAllowance + value);
        }
    
        /**
         * @dev Decrease the calling contract's allowance toward `spender` by `requestedDecrease`. If `token` returns no
         * value, non-reverting calls are assumed to be successful.
         *
         * IMPORTANT: If the token implements ERC-7674 (ERC-20 with temporary allowance), and if the "client"
         * smart contract uses ERC-7674 to set temporary allowances, then the "client" smart contract should avoid using
         * this function. Performing a {safeIncreaseAllowance} or {safeDecreaseAllowance} operation on a token contract
         * that has a non-zero temporary allowance (for that particular owner-spender) will result in unexpected behavior.
         */
        function safeDecreaseAllowance(IERC20 token, address spender, uint256 requestedDecrease) internal {
            unchecked {
                uint256 currentAllowance = token.allowance(address(this), spender);
                if (currentAllowance < requestedDecrease) {
                    revert SafeERC20FailedDecreaseAllowance(spender, currentAllowance, requestedDecrease);
                }
                forceApprove(token, spender, currentAllowance - requestedDecrease);
            }
        }
    
        /**
         * @dev Set the calling contract's allowance toward `spender` to `value`. If `token` returns no value,
         * non-reverting calls are assumed to be successful. Meant to be used with tokens that require the approval
         * to be set to zero before setting it to a non-zero value, such as USDT.
         *
         * NOTE: If the token implements ERC-7674, this function will not modify any temporary allowance. This function
         * only sets the "standard" allowance. Any temporary allowance will remain active, in addition to the value being
         * set here.
         */
        function forceApprove(IERC20 token, address spender, uint256 value) internal {
            bytes memory approvalCall = abi.encodeCall(token.approve, (spender, value));
    
            if (!_callOptionalReturnBool(token, approvalCall)) {
                _callOptionalReturn(token, abi.encodeCall(token.approve, (spender, 0)));
                _callOptionalReturn(token, approvalCall);
            }
        }
    
        /**
         * @dev Performs an {ERC1363} transferAndCall, with a fallback to the simple {ERC20} transfer if the target has no
         * code. This can be used to implement an {ERC721}-like safe transfer that rely on {ERC1363} checks when
         * targeting contracts.
         *
         * Reverts if the returned value is other than `true`.
         */
        function transferAndCallRelaxed(IERC1363 token, address to, uint256 value, bytes memory data) internal {
            if (to.code.length == 0) {
                safeTransfer(token, to, value);
            } else if (!token.transferAndCall(to, value, data)) {
                revert SafeERC20FailedOperation(address(token));
            }
        }
    
        /**
         * @dev Performs an {ERC1363} transferFromAndCall, with a fallback to the simple {ERC20} transferFrom if the target
         * has no code. This can be used to implement an {ERC721}-like safe transfer that rely on {ERC1363} checks when
         * targeting contracts.
         *
         * Reverts if the returned value is other than `true`.
         */
        function transferFromAndCallRelaxed(
            IERC1363 token,
            address from,
            address to,
            uint256 value,
            bytes memory data
        ) internal {
            if (to.code.length == 0) {
                safeTransferFrom(token, from, to, value);
            } else if (!token.transferFromAndCall(from, to, value, data)) {
                revert SafeERC20FailedOperation(address(token));
            }
        }
    
        /**
         * @dev Performs an {ERC1363} approveAndCall, with a fallback to the simple {ERC20} approve if the target has no
         * code. This can be used to implement an {ERC721}-like safe transfer that rely on {ERC1363} checks when
         * targeting contracts.
         *
         * NOTE: When the recipient address (`to`) has no code (i.e. is an EOA), this function behaves as {forceApprove}.
         * Opposedly, when the recipient address (`to`) has code, this function only attempts to call {ERC1363-approveAndCall}
         * once without retrying, and relies on the returned value to be true.
         *
         * Reverts if the returned value is other than `true`.
         */
        function approveAndCallRelaxed(IERC1363 token, address to, uint256 value, bytes memory data) internal {
            if (to.code.length == 0) {
                forceApprove(token, to, value);
            } else if (!token.approveAndCall(to, value, data)) {
                revert SafeERC20FailedOperation(address(token));
            }
        }
    
        /**
         * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
         * on the return value: the return value is optional (but if data is returned, it must not be false).
         * @param token The token targeted by the call.
         * @param data The call data (encoded using abi.encode or one of its variants).
         *
         * This is a variant of {_callOptionalReturnBool} that reverts if call fails to meet the requirements.
         */
        function _callOptionalReturn(IERC20 token, bytes memory data) private {
            uint256 returnSize;
            uint256 returnValue;
            assembly ("memory-safe") {
                let success := call(gas(), token, 0, add(data, 0x20), mload(data), 0, 0x20)
                // bubble errors
                if iszero(success) {
                    let ptr := mload(0x40)
                    returndatacopy(ptr, 0, returndatasize())
                    revert(ptr, returndatasize())
                }
                returnSize := returndatasize()
                returnValue := mload(0)
            }
    
            if (returnSize == 0 ? address(token).code.length == 0 : returnValue != 1) {
                revert SafeERC20FailedOperation(address(token));
            }
        }
    
        /**
         * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
         * on the return value: the return value is optional (but if data is returned, it must not be false).
         * @param token The token targeted by the call.
         * @param data The call data (encoded using abi.encode or one of its variants).
         *
         * This is a variant of {_callOptionalReturn} that silently catches all reverts and returns a bool instead.
         */
        function _callOptionalReturnBool(IERC20 token, bytes memory data) private returns (bool) {
            bool success;
            uint256 returnSize;
            uint256 returnValue;
            assembly ("memory-safe") {
                success := call(gas(), token, 0, add(data, 0x20), mload(data), 0, 0x20)
                returnSize := returndatasize()
                returnValue := mload(0)
            }
            return success && (returnSize == 0 ? address(token).code.length > 0 : returnValue == 1);
        }
    }
    
    // File: @openzeppelin/contracts/utils/Pausable.sol
    
    
    // OpenZeppelin Contracts (last updated v5.3.0) (utils/Pausable.sol)
    
    pragma solidity ^0.8.20;
    
    
    /**
     * @dev Contract module which allows children to implement an emergency stop
     * mechanism that can be triggered by an authorized account.
     *
     * This module is used through inheritance. It will make available the
     * modifiers `whenNotPaused` and `whenPaused`, which can be applied to
     * the functions of your contract. Note that they will not be pausable by
     * simply including this module, only once the modifiers are put in place.
     */
    abstract contract Pausable is Context {
        bool private _paused;
    
        /**
         * @dev Emitted when the pause is triggered by `account`.
         */
        event Paused(address account);
    
        /**
         * @dev Emitted when the pause is lifted by `account`.
         */
        event Unpaused(address account);
    
        /**
         * @dev The operation failed because the contract is paused.
         */
        error EnforcedPause();
    
        /**
         * @dev The operation failed because the contract is not paused.
         */
        error ExpectedPause();
    
        /**
         * @dev Modifier to make a function callable only when the contract is not paused.
         *
         * Requirements:
         *
         * - The contract must not be paused.
         */
        modifier whenNotPaused() {
            _requireNotPaused();
            _;
        }
    
        /**
         * @dev Modifier to make a function callable only when the contract is paused.
         *
         * Requirements:
         *
         * - The contract must be paused.
         */
        modifier whenPaused() {
            _requirePaused();
            _;
        }
    
        /**
         * @dev Returns true if the contract is paused, and false otherwise.
         */
        function paused() public view virtual returns (bool) {
            return _paused;
        }
    
        /**
         * @dev Throws if the contract is paused.
         */
        function _requireNotPaused() internal view virtual {
            if (paused()) {
                revert EnforcedPause();
            }
        }
    
        /**
         * @dev Throws if the contract is not paused.
         */
        function _requirePaused() internal view virtual {
            if (!paused()) {
                revert ExpectedPause();
            }
        }
    
        /**
         * @dev Triggers stopped state.
         *
         * Requirements:
         *
         * - The contract must not be paused.
         */
        function _pause() internal virtual whenNotPaused {
            _paused = true;
            emit Paused(_msgSender());
        }
    
        /**
         * @dev Returns to normal state.
         *
         * Requirements:
         *
         * - The contract must be paused.
         */
        function _unpause() internal virtual whenPaused {
            _paused = false;
            emit Unpaused(_msgSender());
        }
    }
    
    // File: @openzeppelin/contracts/utils/ReentrancyGuard.sol
    
    
    // OpenZeppelin Contracts (last updated v5.1.0) (utils/ReentrancyGuard.sol)
    
    pragma solidity ^0.8.20;
    
    /**
     * @dev Contract module that helps prevent reentrant calls to a function.
     *
     * Inheriting from `ReentrancyGuard` will make the {nonReentrant} modifier
     * available, which can be applied to functions to make sure there are no nested
     * (reentrant) calls to them.
     *
     * Note that because there is a single `nonReentrant` guard, functions marked as
     * `nonReentrant` may not call one another. This can be worked around by making
     * those functions `private`, and then adding `external` `nonReentrant` entry
     * points to them.
     *
     * TIP: If EIP-1153 (transient storage) is available on the chain you're deploying at,
     * consider using {ReentrancyGuardTransient} instead.
     *
     * TIP: If you would like to learn more about reentrancy and alternative ways
     * to protect against it, check out our blog post
     * https://blog.openzeppelin.com/reentrancy-after-istanbul/[Reentrancy After Istanbul].
     */
    abstract contract ReentrancyGuard {
        // Booleans are more expensive than uint256 or any type that takes up a full
        // word because each write operation emits an extra SLOAD to first read the
        // slot's contents, replace the bits taken up by the boolean, and then write
        // back. This is the compiler's defense against contract upgrades and
        // pointer aliasing, and it cannot be disabled.
    
        // The values being non-zero value makes deployment a bit more expensive,
        // but in exchange the refund on every call to nonReentrant will be lower in
        // amount. Since refunds are capped to a percentage of the total
        // transaction's gas, it is best to keep them low in cases like this one, to
        // increase the likelihood of the full refund coming into effect.
        uint256 private constant NOT_ENTERED = 1;
        uint256 private constant ENTERED = 2;
    
        uint256 private _status;
    
        /**
         * @dev Unauthorized reentrant call.
         */
        error ReentrancyGuardReentrantCall();
    
        constructor() {
            _status = NOT_ENTERED;
        }
    
        /**
         * @dev Prevents a contract from calling itself, directly or indirectly.
         * Calling a `nonReentrant` function from another `nonReentrant`
         * function is not supported. It is possible to prevent this from happening
         * by making the `nonReentrant` function external, and making it call a
         * `private` function that does the actual work.
         */
        modifier nonReentrant() {
            _nonReentrantBefore();
            _;
            _nonReentrantAfter();
        }
    
        function _nonReentrantBefore() private {
            // On the first call to nonReentrant, _status will be NOT_ENTERED
            if (_status == ENTERED) {
                revert ReentrancyGuardReentrantCall();
            }
    
            // Any calls to nonReentrant after this point will fail
            _status = ENTERED;
        }
    
        function _nonReentrantAfter() private {
            // By storing the original value once again, a refund is triggered (see
            // https://eips.ethereum.org/EIPS/eip-2200)
            _status = NOT_ENTERED;
        }
    
        /**
         * @dev Returns true if the reentrancy guard is currently set to "entered", which indicates there is a
         * `nonReentrant` function in the call stack.
         */
        function _reentrancyGuardEntered() internal view returns (bool) {
            return _status == ENTERED;
        }
    }
    
    // File: @openzeppelin/contracts/utils/Panic.sol
    
    
    // OpenZeppelin Contracts (last updated v5.1.0) (utils/Panic.sol)
    
    pragma solidity ^0.8.20;
    
    /**
     * @dev Helper library for emitting standardized panic codes.
     *
     * ```solidity
     * contract Example {
     *      using Panic for uint256;
     *
     *      // Use any of the declared internal constants
     *      function foo() { Panic.GENERIC.panic(); }
     *
     *      // Alternatively
     *      function foo() { Panic.panic(Panic.GENERIC); }
     * }
     * ```
     *
     * Follows the list from https://github.com/ethereum/solidity/blob/v0.8.24/libsolutil/ErrorCodes.h[libsolutil].
     *
     * _Available since v5.1._
     */
    // slither-disable-next-line unused-state
    library Panic {
        /// @dev generic / unspecified error
        uint256 internal constant GENERIC = 0x00;
        /// @dev used by the assert() builtin
        uint256 internal constant ASSERT = 0x01;
        /// @dev arithmetic underflow or overflow
        uint256 internal constant UNDER_OVERFLOW = 0x11;
        /// @dev division or modulo by zero
        uint256 internal constant DIVISION_BY_ZERO = 0x12;
        /// @dev enum conversion error
        uint256 internal constant ENUM_CONVERSION_ERROR = 0x21;
        /// @dev invalid encoding in storage
        uint256 internal constant STORAGE_ENCODING_ERROR = 0x22;
        /// @dev empty array pop
        uint256 internal constant EMPTY_ARRAY_POP = 0x31;
        /// @dev array out of bounds access
        uint256 internal constant ARRAY_OUT_OF_BOUNDS = 0x32;
        /// @dev resource error (too large allocation or too large array)
        uint256 internal constant RESOURCE_ERROR = 0x41;
        /// @dev calling invalid internal function
        uint256 internal constant INVALID_INTERNAL_FUNCTION = 0x51;
    
        /// @dev Reverts with a panic code. Recommended to use with
        /// the internal constants with predefined codes.
        function panic(uint256 code) internal pure {
            assembly ("memory-safe") {
                mstore(0x00, 0x4e487b71)
                mstore(0x20, code)
                revert(0x1c, 0x24)
            }
        }
    }
    
    // File: @openzeppelin/contracts/utils/math/SafeCast.sol
    
    
    // OpenZeppelin Contracts (last updated v5.1.0) (utils/math/SafeCast.sol)
    // This file was procedurally generated from scripts/generate/templates/SafeCast.js.
    
    pragma solidity ^0.8.20;
    
    /**
     * @dev Wrappers over Solidity's uintXX/intXX/bool casting operators with added overflow
     * checks.
     *
     * Downcasting from uint256/int256 in Solidity does not revert on overflow. This can
     * easily result in undesired exploitation or bugs, since developers usually
     * assume that overflows raise errors. `SafeCast` restores this intuition by
     * reverting the transaction when such an operation overflows.
     *
     * Using this library instead of the unchecked operations eliminates an entire
     * class of bugs, so it's recommended to use it always.
     */
    library SafeCast {
        /**
         * @dev Value doesn't fit in an uint of `bits` size.
         */
        error SafeCastOverflowedUintDowncast(uint8 bits, uint256 value);
    
        /**
         * @dev An int value doesn't fit in an uint of `bits` size.
         */
        error SafeCastOverflowedIntToUint(int256 value);
    
        /**
         * @dev Value doesn't fit in an int of `bits` size.
         */
        error SafeCastOverflowedIntDowncast(uint8 bits, int256 value);
    
        /**
         * @dev An uint value doesn't fit in an int of `bits` size.
         */
        error SafeCastOverflowedUintToInt(uint256 value);
    
        /**
         * @dev Returns the downcasted uint248 from uint256, reverting on
         * overflow (when the input is greater than largest uint248).
         *
         * Counterpart to Solidity's `uint248` operator.
         *
         * Requirements:
         *
         * - input must fit into 248 bits
         */
        function toUint248(uint256 value) internal pure returns (uint248) {
            if (value > type(uint248).max) {
                revert SafeCastOverflowedUintDowncast(248, value);
            }
            return uint248(value);
        }
    
        /**
         * @dev Returns the downcasted uint240 from uint256, reverting on
         * overflow (when the input is greater than largest uint240).
         *
         * Counterpart to Solidity's `uint240` operator.
         *
         * Requirements:
         *
         * - input must fit into 240 bits
         */
        function toUint240(uint256 value) internal pure returns (uint240) {
            if (value > type(uint240).max) {
                revert SafeCastOverflowedUintDowncast(240, value);
            }
            return uint240(value);
        }
    
        /**
         * @dev Returns the downcasted uint232 from uint256, reverting on
         * overflow (when the input is greater than largest uint232).
         *
         * Counterpart to Solidity's `uint232` operator.
         *
         * Requirements:
         *
         * - input must fit into 232 bits
         */
        function toUint232(uint256 value) internal pure returns (uint232) {
            if (value > type(uint232).max) {
                revert SafeCastOverflowedUintDowncast(232, value);
            }
            return uint232(value);
        }
    
        /**
         * @dev Returns the downcasted uint224 from uint256, reverting on
         * overflow (when the input is greater than largest uint224).
         *
         * Counterpart to Solidity's `uint224` operator.
         *
         * Requirements:
         *
         * - input must fit into 224 bits
         */
        function toUint224(uint256 value) internal pure returns (uint224) {
            if (value > type(uint224).max) {
                revert SafeCastOverflowedUintDowncast(224, value);
            }
            return uint224(value);
        }
    
        /**
         * @dev Returns the downcasted uint216 from uint256, reverting on
         * overflow (when the input is greater than largest uint216).
         *
         * Counterpart to Solidity's `uint216` operator.
         *
         * Requirements:
         *
         * - input must fit into 216 bits
         */
        function toUint216(uint256 value) internal pure returns (uint216) {
            if (value > type(uint216).max) {
                revert SafeCastOverflowedUintDowncast(216, value);
            }
            return uint216(value);
        }
    
        /**
         * @dev Returns the downcasted uint208 from uint256, reverting on
         * overflow (when the input is greater than largest uint208).
         *
         * Counterpart to Solidity's `uint208` operator.
         *
         * Requirements:
         *
         * - input must fit into 208 bits
         */
        function toUint208(uint256 value) internal pure returns (uint208) {
            if (value > type(uint208).max) {
                revert SafeCastOverflowedUintDowncast(208, value);
            }
            return uint208(value);
        }
    
        /**
         * @dev Returns the downcasted uint200 from uint256, reverting on
         * overflow (when the input is greater than largest uint200).
         *
         * Counterpart to Solidity's `uint200` operator.
         *
         * Requirements:
         *
         * - input must fit into 200 bits
         */
        function toUint200(uint256 value) internal pure returns (uint200) {
            if (value > type(uint200).max) {
                revert SafeCastOverflowedUintDowncast(200, value);
            }
            return uint200(value);
        }
    
        /**
         * @dev Returns the downcasted uint192 from uint256, reverting on
         * overflow (when the input is greater than largest uint192).
         *
         * Counterpart to Solidity's `uint192` operator.
         *
         * Requirements:
         *
         * - input must fit into 192 bits
         */
        function toUint192(uint256 value) internal pure returns (uint192) {
            if (value > type(uint192).max) {
                revert SafeCastOverflowedUintDowncast(192, value);
            }
            return uint192(value);
        }
    
        /**
         * @dev Returns the downcasted uint184 from uint256, reverting on
         * overflow (when the input is greater than largest uint184).
         *
         * Counterpart to Solidity's `uint184` operator.
         *
         * Requirements:
         *
         * - input must fit into 184 bits
         */
        function toUint184(uint256 value) internal pure returns (uint184) {
            if (value > type(uint184).max) {
                revert SafeCastOverflowedUintDowncast(184, value);
            }
            return uint184(value);
        }
    
        /**
         * @dev Returns the downcasted uint176 from uint256, reverting on
         * overflow (when the input is greater than largest uint176).
         *
         * Counterpart to Solidity's `uint176` operator.
         *
         * Requirements:
         *
         * - input must fit into 176 bits
         */
        function toUint176(uint256 value) internal pure returns (uint176) {
            if (value > type(uint176).max) {
                revert SafeCastOverflowedUintDowncast(176, value);
            }
            return uint176(value);
        }
    
        /**
         * @dev Returns the downcasted uint168 from uint256, reverting on
         * overflow (when the input is greater than largest uint168).
         *
         * Counterpart to Solidity's `uint168` operator.
         *
         * Requirements:
         *
         * - input must fit into 168 bits
         */
        function toUint168(uint256 value) internal pure returns (uint168) {
            if (value > type(uint168).max) {
                revert SafeCastOverflowedUintDowncast(168, value);
            }
            return uint168(value);
        }
    
        /**
         * @dev Returns the downcasted uint160 from uint256, reverting on
         * overflow (when the input is greater than largest uint160).
         *
         * Counterpart to Solidity's `uint160` operator.
         *
         * Requirements:
         *
         * - input must fit into 160 bits
         */
        function toUint160(uint256 value) internal pure returns (uint160) {
            if (value > type(uint160).max) {
                revert SafeCastOverflowedUintDowncast(160, value);
            }
            return uint160(value);
        }
    
        /**
         * @dev Returns the downcasted uint152 from uint256, reverting on
         * overflow (when the input is greater than largest uint152).
         *
         * Counterpart to Solidity's `uint152` operator.
         *
         * Requirements:
         *
         * - input must fit into 152 bits
         */
        function toUint152(uint256 value) internal pure returns (uint152) {
            if (value > type(uint152).max) {
                revert SafeCastOverflowedUintDowncast(152, value);
            }
            return uint152(value);
        }
    
        /**
         * @dev Returns the downcasted uint144 from uint256, reverting on
         * overflow (when the input is greater than largest uint144).
         *
         * Counterpart to Solidity's `uint144` operator.
         *
         * Requirements:
         *
         * - input must fit into 144 bits
         */
        function toUint144(uint256 value) internal pure returns (uint144) {
            if (value > type(uint144).max) {
                revert SafeCastOverflowedUintDowncast(144, value);
            }
            return uint144(value);
        }
    
        /**
         * @dev Returns the downcasted uint136 from uint256, reverting on
         * overflow (when the input is greater than largest uint136).
         *
         * Counterpart to Solidity's `uint136` operator.
         *
         * Requirements:
         *
         * - input must fit into 136 bits
         */
        function toUint136(uint256 value) internal pure returns (uint136) {
            if (value > type(uint136).max) {
                revert SafeCastOverflowedUintDowncast(136, value);
            }
            return uint136(value);
        }
    
        /**
         * @dev Returns the downcasted uint128 from uint256, reverting on
         * overflow (when the input is greater than largest uint128).
         *
         * Counterpart to Solidity's `uint128` operator.
         *
         * Requirements:
         *
         * - input must fit into 128 bits
         */
        function toUint128(uint256 value) internal pure returns (uint128) {
            if (value > type(uint128).max) {
                revert SafeCastOverflowedUintDowncast(128, value);
            }
            return uint128(value);
        }
    
        /**
         * @dev Returns the downcasted uint120 from uint256, reverting on
         * overflow (when the input is greater than largest uint120).
         *
         * Counterpart to Solidity's `uint120` operator.
         *
         * Requirements:
         *
         * - input must fit into 120 bits
         */
        function toUint120(uint256 value) internal pure returns (uint120) {
            if (value > type(uint120).max) {
                revert SafeCastOverflowedUintDowncast(120, value);
            }
            return uint120(value);
        }
    
        /**
         * @dev Returns the downcasted uint112 from uint256, reverting on
         * overflow (when the input is greater than largest uint112).
         *
         * Counterpart to Solidity's `uint112` operator.
         *
         * Requirements:
         *
         * - input must fit into 112 bits
         */
        function toUint112(uint256 value) internal pure returns (uint112) {
            if (value > type(uint112).max) {
                revert SafeCastOverflowedUintDowncast(112, value);
            }
            return uint112(value);
        }
    
        /**
         * @dev Returns the downcasted uint104 from uint256, reverting on
         * overflow (when the input is greater than largest uint104).
         *
         * Counterpart to Solidity's `uint104` operator.
         *
         * Requirements:
         *
         * - input must fit into 104 bits
         */
        function toUint104(uint256 value) internal pure returns (uint104) {
            if (value > type(uint104).max) {
                revert SafeCastOverflowedUintDowncast(104, value);
            }
            return uint104(value);
        }
    
        /**
         * @dev Returns the downcasted uint96 from uint256, reverting on
         * overflow (when the input is greater than largest uint96).
         *
         * Counterpart to Solidity's `uint96` operator.
         *
         * Requirements:
         *
         * - input must fit into 96 bits
         */
        function toUint96(uint256 value) internal pure returns (uint96) {
            if (value > type(uint96).max) {
                revert SafeCastOverflowedUintDowncast(96, value);
            }
            return uint96(value);
        }
    
        /**
         * @dev Returns the downcasted uint88 from uint256, reverting on
         * overflow (when the input is greater than largest uint88).
         *
         * Counterpart to Solidity's `uint88` operator.
         *
         * Requirements:
         *
         * - input must fit into 88 bits
         */
        function toUint88(uint256 value) internal pure returns (uint88) {
            if (value > type(uint88).max) {
                revert SafeCastOverflowedUintDowncast(88, value);
            }
            return uint88(value);
        }
    
        /**
         * @dev Returns the downcasted uint80 from uint256, reverting on
         * overflow (when the input is greater than largest uint80).
         *
         * Counterpart to Solidity's `uint80` operator.
         *
         * Requirements:
         *
         * - input must fit into 80 bits
         */
        function toUint80(uint256 value) internal pure returns (uint80) {
            if (value > type(uint80).max) {
                revert SafeCastOverflowedUintDowncast(80, value);
            }
            return uint80(value);
        }
    
        /**
         * @dev Returns the downcasted uint72 from uint256, reverting on
         * overflow (when the input is greater than largest uint72).
         *
         * Counterpart to Solidity's `uint72` operator.
         *
         * Requirements:
         *
         * - input must fit into 72 bits
         */
        function toUint72(uint256 value) internal pure returns (uint72) {
            if (value > type(uint72).max) {
                revert SafeCastOverflowedUintDowncast(72, value);
            }
            return uint72(value);
        }
    
        /**
         * @dev Returns the downcasted uint64 from uint256, reverting on
         * overflow (when the input is greater than largest uint64).
         *
         * Counterpart to Solidity's `uint64` operator.
         *
         * Requirements:
         *
         * - input must fit into 64 bits
         */
        function toUint64(uint256 value) internal pure returns (uint64) {
            if (value > type(uint64).max) {
                revert SafeCastOverflowedUintDowncast(64, value);
            }
            return uint64(value);
        }
    
        /**
         * @dev Returns the downcasted uint56 from uint256, reverting on
         * overflow (when the input is greater than largest uint56).
         *
         * Counterpart to Solidity's `uint56` operator.
         *
         * Requirements:
         *
         * - input must fit into 56 bits
         */
        function toUint56(uint256 value) internal pure returns (uint56) {
            if (value > type(uint56).max) {
                revert SafeCastOverflowedUintDowncast(56, value);
            }
            return uint56(value);
        }
    
        /**
         * @dev Returns the downcasted uint48 from uint256, reverting on
         * overflow (when the input is greater than largest uint48).
         *
         * Counterpart to Solidity's `uint48` operator.
         *
         * Requirements:
         *
         * - input must fit into 48 bits
         */
        function toUint48(uint256 value) internal pure returns (uint48) {
            if (value > type(uint48).max) {
                revert SafeCastOverflowedUintDowncast(48, value);
            }
            return uint48(value);
        }
    
        /**
         * @dev Returns the downcasted uint40 from uint256, reverting on
         * overflow (when the input is greater than largest uint40).
         *
         * Counterpart to Solidity's `uint40` operator.
         *
         * Requirements:
         *
         * - input must fit into 40 bits
         */
        function toUint40(uint256 value) internal pure returns (uint40) {
            if (value > type(uint40).max) {
                revert SafeCastOverflowedUintDowncast(40, value);
            }
            return uint40(value);
        }
    
        /**
         * @dev Returns the downcasted uint32 from uint256, reverting on
         * overflow (when the input is greater than largest uint32).
         *
         * Counterpart to Solidity's `uint32` operator.
         *
         * Requirements:
         *
         * - input must fit into 32 bits
         */
        function toUint32(uint256 value) internal pure returns (uint32) {
            if (value > type(uint32).max) {
                revert SafeCastOverflowedUintDowncast(32, value);
            }
            return uint32(value);
        }
    
        /**
         * @dev Returns the downcasted uint24 from uint256, reverting on
         * overflow (when the input is greater than largest uint24).
         *
         * Counterpart to Solidity's `uint24` operator.
         *
         * Requirements:
         *
         * - input must fit into 24 bits
         */
        function toUint24(uint256 value) internal pure returns (uint24) {
            if (value > type(uint24).max) {
                revert SafeCastOverflowedUintDowncast(24, value);
            }
            return uint24(value);
        }
    
        /**
         * @dev Returns the downcasted uint16 from uint256, reverting on
         * overflow (when the input is greater than largest uint16).
         *
         * Counterpart to Solidity's `uint16` operator.
         *
         * Requirements:
         *
         * - input must fit into 16 bits
         */
        function toUint16(uint256 value) internal pure returns (uint16) {
            if (value > type(uint16).max) {
                revert SafeCastOverflowedUintDowncast(16, value);
            }
            return uint16(value);
        }
    
        /**
         * @dev Returns the downcasted uint8 from uint256, reverting on
         * overflow (when the input is greater than largest uint8).
         *
         * Counterpart to Solidity's `uint8` operator.
         *
         * Requirements:
         *
         * - input must fit into 8 bits
         */
        function toUint8(uint256 value) internal pure returns (uint8) {
            if (value > type(uint8).max) {
                revert SafeCastOverflowedUintDowncast(8, value);
            }
            return uint8(value);
        }
    
        /**
         * @dev Converts a signed int256 into an unsigned uint256.
         *
         * Requirements:
         *
         * - input must be greater than or equal to 0.
         */
        function toUint256(int256 value) internal pure returns (uint256) {
            if (value < 0) {
                revert SafeCastOverflowedIntToUint(value);
            }
            return uint256(value);
        }
    
        /**
         * @dev Returns the downcasted int248 from int256, reverting on
         * overflow (when the input is less than smallest int248 or
         * greater than largest int248).
         *
         * Counterpart to Solidity's `int248` operator.
         *
         * Requirements:
         *
         * - input must fit into 248 bits
         */
        function toInt248(int256 value) internal pure returns (int248 downcasted) {
            downcasted = int248(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(248, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int240 from int256, reverting on
         * overflow (when the input is less than smallest int240 or
         * greater than largest int240).
         *
         * Counterpart to Solidity's `int240` operator.
         *
         * Requirements:
         *
         * - input must fit into 240 bits
         */
        function toInt240(int256 value) internal pure returns (int240 downcasted) {
            downcasted = int240(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(240, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int232 from int256, reverting on
         * overflow (when the input is less than smallest int232 or
         * greater than largest int232).
         *
         * Counterpart to Solidity's `int232` operator.
         *
         * Requirements:
         *
         * - input must fit into 232 bits
         */
        function toInt232(int256 value) internal pure returns (int232 downcasted) {
            downcasted = int232(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(232, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int224 from int256, reverting on
         * overflow (when the input is less than smallest int224 or
         * greater than largest int224).
         *
         * Counterpart to Solidity's `int224` operator.
         *
         * Requirements:
         *
         * - input must fit into 224 bits
         */
        function toInt224(int256 value) internal pure returns (int224 downcasted) {
            downcasted = int224(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(224, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int216 from int256, reverting on
         * overflow (when the input is less than smallest int216 or
         * greater than largest int216).
         *
         * Counterpart to Solidity's `int216` operator.
         *
         * Requirements:
         *
         * - input must fit into 216 bits
         */
        function toInt216(int256 value) internal pure returns (int216 downcasted) {
            downcasted = int216(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(216, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int208 from int256, reverting on
         * overflow (when the input is less than smallest int208 or
         * greater than largest int208).
         *
         * Counterpart to Solidity's `int208` operator.
         *
         * Requirements:
         *
         * - input must fit into 208 bits
         */
        function toInt208(int256 value) internal pure returns (int208 downcasted) {
            downcasted = int208(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(208, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int200 from int256, reverting on
         * overflow (when the input is less than smallest int200 or
         * greater than largest int200).
         *
         * Counterpart to Solidity's `int200` operator.
         *
         * Requirements:
         *
         * - input must fit into 200 bits
         */
        function toInt200(int256 value) internal pure returns (int200 downcasted) {
            downcasted = int200(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(200, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int192 from int256, reverting on
         * overflow (when the input is less than smallest int192 or
         * greater than largest int192).
         *
         * Counterpart to Solidity's `int192` operator.
         *
         * Requirements:
         *
         * - input must fit into 192 bits
         */
        function toInt192(int256 value) internal pure returns (int192 downcasted) {
            downcasted = int192(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(192, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int184 from int256, reverting on
         * overflow (when the input is less than smallest int184 or
         * greater than largest int184).
         *
         * Counterpart to Solidity's `int184` operator.
         *
         * Requirements:
         *
         * - input must fit into 184 bits
         */
        function toInt184(int256 value) internal pure returns (int184 downcasted) {
            downcasted = int184(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(184, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int176 from int256, reverting on
         * overflow (when the input is less than smallest int176 or
         * greater than largest int176).
         *
         * Counterpart to Solidity's `int176` operator.
         *
         * Requirements:
         *
         * - input must fit into 176 bits
         */
        function toInt176(int256 value) internal pure returns (int176 downcasted) {
            downcasted = int176(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(176, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int168 from int256, reverting on
         * overflow (when the input is less than smallest int168 or
         * greater than largest int168).
         *
         * Counterpart to Solidity's `int168` operator.
         *
         * Requirements:
         *
         * - input must fit into 168 bits
         */
        function toInt168(int256 value) internal pure returns (int168 downcasted) {
            downcasted = int168(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(168, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int160 from int256, reverting on
         * overflow (when the input is less than smallest int160 or
         * greater than largest int160).
         *
         * Counterpart to Solidity's `int160` operator.
         *
         * Requirements:
         *
         * - input must fit into 160 bits
         */
        function toInt160(int256 value) internal pure returns (int160 downcasted) {
            downcasted = int160(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(160, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int152 from int256, reverting on
         * overflow (when the input is less than smallest int152 or
         * greater than largest int152).
         *
         * Counterpart to Solidity's `int152` operator.
         *
         * Requirements:
         *
         * - input must fit into 152 bits
         */
        function toInt152(int256 value) internal pure returns (int152 downcasted) {
            downcasted = int152(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(152, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int144 from int256, reverting on
         * overflow (when the input is less than smallest int144 or
         * greater than largest int144).
         *
         * Counterpart to Solidity's `int144` operator.
         *
         * Requirements:
         *
         * - input must fit into 144 bits
         */
        function toInt144(int256 value) internal pure returns (int144 downcasted) {
            downcasted = int144(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(144, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int136 from int256, reverting on
         * overflow (when the input is less than smallest int136 or
         * greater than largest int136).
         *
         * Counterpart to Solidity's `int136` operator.
         *
         * Requirements:
         *
         * - input must fit into 136 bits
         */
        function toInt136(int256 value) internal pure returns (int136 downcasted) {
            downcasted = int136(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(136, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int128 from int256, reverting on
         * overflow (when the input is less than smallest int128 or
         * greater than largest int128).
         *
         * Counterpart to Solidity's `int128` operator.
         *
         * Requirements:
         *
         * - input must fit into 128 bits
         */
        function toInt128(int256 value) internal pure returns (int128 downcasted) {
            downcasted = int128(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(128, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int120 from int256, reverting on
         * overflow (when the input is less than smallest int120 or
         * greater than largest int120).
         *
         * Counterpart to Solidity's `int120` operator.
         *
         * Requirements:
         *
         * - input must fit into 120 bits
         */
        function toInt120(int256 value) internal pure returns (int120 downcasted) {
            downcasted = int120(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(120, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int112 from int256, reverting on
         * overflow (when the input is less than smallest int112 or
         * greater than largest int112).
         *
         * Counterpart to Solidity's `int112` operator.
         *
         * Requirements:
         *
         * - input must fit into 112 bits
         */
        function toInt112(int256 value) internal pure returns (int112 downcasted) {
            downcasted = int112(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(112, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int104 from int256, reverting on
         * overflow (when the input is less than smallest int104 or
         * greater than largest int104).
         *
         * Counterpart to Solidity's `int104` operator.
         *
         * Requirements:
         *
         * - input must fit into 104 bits
         */
        function toInt104(int256 value) internal pure returns (int104 downcasted) {
            downcasted = int104(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(104, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int96 from int256, reverting on
         * overflow (when the input is less than smallest int96 or
         * greater than largest int96).
         *
         * Counterpart to Solidity's `int96` operator.
         *
         * Requirements:
         *
         * - input must fit into 96 bits
         */
        function toInt96(int256 value) internal pure returns (int96 downcasted) {
            downcasted = int96(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(96, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int88 from int256, reverting on
         * overflow (when the input is less than smallest int88 or
         * greater than largest int88).
         *
         * Counterpart to Solidity's `int88` operator.
         *
         * Requirements:
         *
         * - input must fit into 88 bits
         */
        function toInt88(int256 value) internal pure returns (int88 downcasted) {
            downcasted = int88(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(88, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int80 from int256, reverting on
         * overflow (when the input is less than smallest int80 or
         * greater than largest int80).
         *
         * Counterpart to Solidity's `int80` operator.
         *
         * Requirements:
         *
         * - input must fit into 80 bits
         */
        function toInt80(int256 value) internal pure returns (int80 downcasted) {
            downcasted = int80(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(80, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int72 from int256, reverting on
         * overflow (when the input is less than smallest int72 or
         * greater than largest int72).
         *
         * Counterpart to Solidity's `int72` operator.
         *
         * Requirements:
         *
         * - input must fit into 72 bits
         */
        function toInt72(int256 value) internal pure returns (int72 downcasted) {
            downcasted = int72(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(72, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int64 from int256, reverting on
         * overflow (when the input is less than smallest int64 or
         * greater than largest int64).
         *
         * Counterpart to Solidity's `int64` operator.
         *
         * Requirements:
         *
         * - input must fit into 64 bits
         */
        function toInt64(int256 value) internal pure returns (int64 downcasted) {
            downcasted = int64(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(64, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int56 from int256, reverting on
         * overflow (when the input is less than smallest int56 or
         * greater than largest int56).
         *
         * Counterpart to Solidity's `int56` operator.
         *
         * Requirements:
         *
         * - input must fit into 56 bits
         */
        function toInt56(int256 value) internal pure returns (int56 downcasted) {
            downcasted = int56(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(56, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int48 from int256, reverting on
         * overflow (when the input is less than smallest int48 or
         * greater than largest int48).
         *
         * Counterpart to Solidity's `int48` operator.
         *
         * Requirements:
         *
         * - input must fit into 48 bits
         */
        function toInt48(int256 value) internal pure returns (int48 downcasted) {
            downcasted = int48(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(48, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int40 from int256, reverting on
         * overflow (when the input is less than smallest int40 or
         * greater than largest int40).
         *
         * Counterpart to Solidity's `int40` operator.
         *
         * Requirements:
         *
         * - input must fit into 40 bits
         */
        function toInt40(int256 value) internal pure returns (int40 downcasted) {
            downcasted = int40(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(40, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int32 from int256, reverting on
         * overflow (when the input is less than smallest int32 or
         * greater than largest int32).
         *
         * Counterpart to Solidity's `int32` operator.
         *
         * Requirements:
         *
         * - input must fit into 32 bits
         */
        function toInt32(int256 value) internal pure returns (int32 downcasted) {
            downcasted = int32(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(32, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int24 from int256, reverting on
         * overflow (when the input is less than smallest int24 or
         * greater than largest int24).
         *
         * Counterpart to Solidity's `int24` operator.
         *
         * Requirements:
         *
         * - input must fit into 24 bits
         */
        function toInt24(int256 value) internal pure returns (int24 downcasted) {
            downcasted = int24(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(24, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int16 from int256, reverting on
         * overflow (when the input is less than smallest int16 or
         * greater than largest int16).
         *
         * Counterpart to Solidity's `int16` operator.
         *
         * Requirements:
         *
         * - input must fit into 16 bits
         */
        function toInt16(int256 value) internal pure returns (int16 downcasted) {
            downcasted = int16(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(16, value);
            }
        }
    
        /**
         * @dev Returns the downcasted int8 from int256, reverting on
         * overflow (when the input is less than smallest int8 or
         * greater than largest int8).
         *
         * Counterpart to Solidity's `int8` operator.
         *
         * Requirements:
         *
         * - input must fit into 8 bits
         */
        function toInt8(int256 value) internal pure returns (int8 downcasted) {
            downcasted = int8(value);
            if (downcasted != value) {
                revert SafeCastOverflowedIntDowncast(8, value);
            }
        }
    
        /**
         * @dev Converts an unsigned uint256 into a signed int256.
         *
         * Requirements:
         *
         * - input must be less than or equal to maxInt256.
         */
        function toInt256(uint256 value) internal pure returns (int256) {
            // Note: Unsafe cast below is okay because `type(int256).max` is guaranteed to be positive
            if (value > uint256(type(int256).max)) {
                revert SafeCastOverflowedUintToInt(value);
            }
            return int256(value);
        }
    
        /**
         * @dev Cast a boolean (false or true) to a uint256 (0 or 1) with no jump.
         */
        function toUint(bool b) internal pure returns (uint256 u) {
            assembly ("memory-safe") {
                u := iszero(iszero(b))
            }
        }
    }
    
    // File: @openzeppelin/contracts/utils/math/Math.sol
    
    
    // OpenZeppelin Contracts (last updated v5.3.0) (utils/math/Math.sol)
    
    pragma solidity ^0.8.20;
    
    
    
    /**
     * @dev Standard math utilities missing in the Solidity language.
     */
    library Math {
        enum Rounding {
            Floor, // Toward negative infinity
            Ceil, // Toward positive infinity
            Trunc, // Toward zero
            Expand // Away from zero
        }
    
        /**
         * @dev Return the 512-bit addition of two uint256.
         *
         * The result is stored in two 256 variables such that sum = high * 2²⁵⁶ + low.
         */
        function add512(uint256 a, uint256 b) internal pure returns (uint256 high, uint256 low) {
            assembly ("memory-safe") {
                low := add(a, b)
                high := lt(low, a)
            }
        }
    
        /**
         * @dev Return the 512-bit multiplication of two uint256.
         *
         * The result is stored in two 256 variables such that product = high * 2²⁵⁶ + low.
         */
        function mul512(uint256 a, uint256 b) internal pure returns (uint256 high, uint256 low) {
            // 512-bit multiply [high low] = x * y. Compute the product mod 2²⁵⁶ and mod 2²⁵⁶ - 1, then use
            // the Chinese Remainder Theorem to reconstruct the 512 bit result. The result is stored in two 256
            // variables such that product = high * 2²⁵⁶ + low.
            assembly ("memory-safe") {
                let mm := mulmod(a, b, not(0))
                low := mul(a, b)
                high := sub(sub(mm, low), lt(mm, low))
            }
        }
    
        /**
         * @dev Returns the addition of two unsigned integers, with a success flag (no overflow).
         */
        function tryAdd(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
            unchecked {
                uint256 c = a + b;
                success = c >= a;
                result = c * SafeCast.toUint(success);
            }
        }
    
        /**
         * @dev Returns the subtraction of two unsigned integers, with a success flag (no overflow).
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
            unchecked {
                uint256 c = a - b;
                success = c <= a;
                result = c * SafeCast.toUint(success);
            }
        }
    
        /**
         * @dev Returns the multiplication of two unsigned integers, with a success flag (no overflow).
         */
        function tryMul(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
            unchecked {
                uint256 c = a * b;
                assembly ("memory-safe") {
                    // Only true when the multiplication doesn't overflow
                    // (c / a == b) || (a == 0)
                    success := or(eq(div(c, a), b), iszero(a))
                }
                // equivalent to: success ? c : 0
                result = c * SafeCast.toUint(success);
            }
        }
    
        /**
         * @dev Returns the division of two unsigned integers, with a success flag (no division by zero).
         */
        function tryDiv(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
            unchecked {
                success = b > 0;
                assembly ("memory-safe") {
                    // The `DIV` opcode returns zero when the denominator is 0.
                    result := div(a, b)
                }
            }
        }
    
        /**
         * @dev Returns the remainder of dividing two unsigned integers, with a success flag (no division by zero).
         */
        function tryMod(uint256 a, uint256 b) internal pure returns (bool success, uint256 result) {
            unchecked {
                success = b > 0;
                assembly ("memory-safe") {
                    // The `MOD` opcode returns zero when the denominator is 0.
                    result := mod(a, b)
                }
            }
        }
    
        /**
         * @dev Unsigned saturating addition, bounds to `2²⁵⁶ - 1` instead of overflowing.
         */
        function saturatingAdd(uint256 a, uint256 b) internal pure returns (uint256) {
            (bool success, uint256 result) = tryAdd(a, b);
            return ternary(success, result, type(uint256).max);
        }
    
        /**
         * @dev Unsigned saturating subtraction, bounds to zero instead of overflowing.
         */
        function saturatingSub(uint256 a, uint256 b) internal pure returns (uint256) {
            (, uint256 result) = trySub(a, b);
            return result;
        }
    
        /**
         * @dev Unsigned saturating multiplication, bounds to `2²⁵⁶ - 1` instead of overflowing.
         */
        function saturatingMul(uint256 a, uint256 b) internal pure returns (uint256) {
            (bool success, uint256 result) = tryMul(a, b);
            return ternary(success, result, type(uint256).max);
        }
    
        /**
         * @dev Branchless ternary evaluation for `a ? b : c`. Gas costs are constant.
         *
         * IMPORTANT: This function may reduce bytecode size and consume less gas when used standalone.
         * However, the compiler may optimize Solidity ternary operations (i.e. `a ? b : c`) to only compute
         * one branch when needed, making this function more expensive.
         */
        function ternary(bool condition, uint256 a, uint256 b) internal pure returns (uint256) {
            unchecked {
                // branchless ternary works because:
                // b ^ (a ^ b) == a
                // b ^ 0 == b
                return b ^ ((a ^ b) * SafeCast.toUint(condition));
            }
        }
    
        /**
         * @dev Returns the largest of two numbers.
         */
        function max(uint256 a, uint256 b) internal pure returns (uint256) {
            return ternary(a > b, a, b);
        }
    
        /**
         * @dev Returns the smallest of two numbers.
         */
        function min(uint256 a, uint256 b) internal pure returns (uint256) {
            return ternary(a < b, a, b);
        }
    
        /**
         * @dev Returns the average of two numbers. The result is rounded towards
         * zero.
         */
        function average(uint256 a, uint256 b) internal pure returns (uint256) {
            // (a + b) / 2 can overflow.
            return (a & b) + (a ^ b) / 2;
        }
    
        /**
         * @dev Returns the ceiling of the division of two numbers.
         *
         * This differs from standard division with `/` in that it rounds towards infinity instead
         * of rounding towards zero.
         */
        function ceilDiv(uint256 a, uint256 b) internal pure returns (uint256) {
            if (b == 0) {
                // Guarantee the same behavior as in a regular Solidity division.
                Panic.panic(Panic.DIVISION_BY_ZERO);
            }
    
            // The following calculation ensures accurate ceiling division without overflow.
            // Since a is non-zero, (a - 1) / b will not overflow.
            // The largest possible result occurs when (a - 1) / b is type(uint256).max,
            // but the largest value we can obtain is type(uint256).max - 1, which happens
            // when a = type(uint256).max and b = 1.
            unchecked {
                return SafeCast.toUint(a > 0) * ((a - 1) / b + 1);
            }
        }
    
        /**
         * @dev Calculates floor(x * y / denominator) with full precision. Throws if result overflows a uint256 or
         * denominator == 0.
         *
         * Original credit to Remco Bloemen under MIT license (https://xn--2-umb.com/21/muldiv) with further edits by
         * Uniswap Labs also under MIT license.
         */
        function mulDiv(uint256 x, uint256 y, uint256 denominator) internal pure returns (uint256 result) {
            unchecked {
                (uint256 high, uint256 low) = mul512(x, y);
    
                // Handle non-overflow cases, 256 by 256 division.
                if (high == 0) {
                    // Solidity will revert if denominator == 0, unlike the div opcode on its own.
                    // The surrounding unchecked block does not change this fact.
                    // See https://docs.soliditylang.org/en/latest/control-structures.html#checked-or-unchecked-arithmetic.
                    return low / denominator;
                }
    
                // Make sure the result is less than 2²⁵⁶. Also prevents denominator == 0.
                if (denominator <= high) {
                    Panic.panic(ternary(denominator == 0, Panic.DIVISION_BY_ZERO, Panic.UNDER_OVERFLOW));
                }
    
                ///////////////////////////////////////////////
                // 512 by 256 division.
                ///////////////////////////////////////////////
    
                // Make division exact by subtracting the remainder from [high low].
                uint256 remainder;
                assembly ("memory-safe") {
                    // Compute remainder using mulmod.
                    remainder := mulmod(x, y, denominator)
    
                    // Subtract 256 bit number from 512 bit number.
                    high := sub(high, gt(remainder, low))
                    low := sub(low, remainder)
                }
    
                // Factor powers of two out of denominator and compute largest power of two divisor of denominator.
                // Always >= 1. See https://cs.stackexchange.com/q/138556/92363.
    
                uint256 twos = denominator & (0 - denominator);
                assembly ("memory-safe") {
                    // Divide denominator by twos.
                    denominator := div(denominator, twos)
    
                    // Divide [high low] by twos.
                    low := div(low, twos)
    
                    // Flip twos such that it is 2²⁵⁶ / twos. If twos is zero, then it becomes one.
                    twos := add(div(sub(0, twos), twos), 1)
                }
    
                // Shift in bits from high into low.
                low |= high * twos;
    
                // Invert denominator mod 2²⁵⁶. Now that denominator is an odd number, it has an inverse modulo 2²⁵⁶ such
                // that denominator * inv ≡ 1 mod 2²⁵⁶. Compute the inverse by starting with a seed that is correct for
                // four bits. That is, denominator * inv ≡ 1 mod 2⁴.
                uint256 inverse = (3 * denominator) ^ 2;
    
                // Use the Newton-Raphson iteration to improve the precision. Thanks to Hensel's lifting lemma, this also
                // works in modular arithmetic, doubling the correct bits in each step.
                inverse *= 2 - denominator * inverse; // inverse mod 2⁸
                inverse *= 2 - denominator * inverse; // inverse mod 2¹⁶
                inverse *= 2 - denominator * inverse; // inverse mod 2³²
                inverse *= 2 - denominator * inverse; // inverse mod 2⁶⁴
                inverse *= 2 - denominator * inverse; // inverse mod 2¹²⁸
                inverse *= 2 - denominator * inverse; // inverse mod 2²⁵⁶
    
                // Because the division is now exact we can divide by multiplying with the modular inverse of denominator.
                // This will give us the correct result modulo 2²⁵⁶. Since the preconditions guarantee that the outcome is
                // less than 2²⁵⁶, this is the final result. We don't need to compute the high bits of the result and high
                // is no longer required.
                result = low * inverse;
                return result;
            }
        }
    
        /**
         * @dev Calculates x * y / denominator with full precision, following the selected rounding direction.
         */
        function mulDiv(uint256 x, uint256 y, uint256 denominator, Rounding rounding) internal pure returns (uint256) {
            return mulDiv(x, y, denominator) + SafeCast.toUint(unsignedRoundsUp(rounding) && mulmod(x, y, denominator) > 0);
        }
    
        /**
         * @dev Calculates floor(x * y >> n) with full precision. Throws if result overflows a uint256.
         */
        function mulShr(uint256 x, uint256 y, uint8 n) internal pure returns (uint256 result) {
            unchecked {
                (uint256 high, uint256 low) = mul512(x, y);
                if (high >= 1 << n) {
                    Panic.panic(Panic.UNDER_OVERFLOW);
                }
                return (high << (256 - n)) | (low >> n);
            }
        }
    
        /**
         * @dev Calculates x * y >> n with full precision, following the selected rounding direction.
         */
        function mulShr(uint256 x, uint256 y, uint8 n, Rounding rounding) internal pure returns (uint256) {
            return mulShr(x, y, n) + SafeCast.toUint(unsignedRoundsUp(rounding) && mulmod(x, y, 1 << n) > 0);
        }
    
        /**
         * @dev Calculate the modular multiplicative inverse of a number in Z/nZ.
         *
         * If n is a prime, then Z/nZ is a field. In that case all elements are inversible, except 0.
         * If n is not a prime, then Z/nZ is not a field, and some elements might not be inversible.
         *
         * If the input value is not inversible, 0 is returned.
         *
         * NOTE: If you know for sure that n is (big) a prime, it may be cheaper to use Fermat's little theorem and get the
         * inverse using `Math.modExp(a, n - 2, n)`. See {invModPrime}.
         */
        function invMod(uint256 a, uint256 n) internal pure returns (uint256) {
            unchecked {
                if (n == 0) return 0;
    
                // The inverse modulo is calculated using the Extended Euclidean Algorithm (iterative version)
                // Used to compute integers x and y such that: ax + ny = gcd(a, n).
                // When the gcd is 1, then the inverse of a modulo n exists and it's x.
                // ax + ny = 1
                // ax = 1 + (-y)n
                // ax ≡ 1 (mod n) # x is the inverse of a modulo n
    
                // If the remainder is 0 the gcd is n right away.
                uint256 remainder = a % n;
                uint256 gcd = n;
    
                // Therefore the initial coefficients are:
                // ax + ny = gcd(a, n) = n
                // 0a + 1n = n
                int256 x = 0;
                int256 y = 1;
    
                while (remainder != 0) {
                    uint256 quotient = gcd / remainder;
    
                    (gcd, remainder) = (
                        // The old remainder is the next gcd to try.
                        remainder,
                        // Compute the next remainder.
                        // Can't overflow given that (a % gcd) * (gcd // (a % gcd)) <= gcd
                        // where gcd is at most n (capped to type(uint256).max)
                        gcd - remainder * quotient
                    );
    
                    (x, y) = (
                        // Increment the coefficient of a.
                        y,
                        // Decrement the coefficient of n.
                        // Can overflow, but the result is casted to uint256 so that the
                        // next value of y is "wrapped around" to a value between 0 and n - 1.
                        x - y * int256(quotient)
                    );
                }
    
                if (gcd != 1) return 0; // No inverse exists.
                return ternary(x < 0, n - uint256(-x), uint256(x)); // Wrap the result if it's negative.
            }
        }
    
        /**
         * @dev Variant of {invMod}. More efficient, but only works if `p` is known to be a prime greater than `2`.
         *
         * From https://en.wikipedia.org/wiki/Fermat%27s_little_theorem[Fermat's little theorem], we know that if p is
         * prime, then `a**(p-1) ≡ 1 mod p`. As a consequence, we have `a * a**(p-2) ≡ 1 mod p`, which means that
         * `a**(p-2)` is the modular multiplicative inverse of a in Fp.
         *
         * NOTE: this function does NOT check that `p` is a prime greater than `2`.
         */
        function invModPrime(uint256 a, uint256 p) internal view returns (uint256) {
            unchecked {
                return Math.modExp(a, p - 2, p);
            }
        }
    
        /**
         * @dev Returns the modular exponentiation of the specified base, exponent and modulus (b ** e % m)
         *
         * Requirements:
         * - modulus can't be zero
         * - underlying staticcall to precompile must succeed
         *
         * IMPORTANT: The result is only valid if the underlying call succeeds. When using this function, make
         * sure the chain you're using it on supports the precompiled contract for modular exponentiation
         * at address 0x05 as specified in https://eips.ethereum.org/EIPS/eip-198[EIP-198]. Otherwise,
         * the underlying function will succeed given the lack of a revert, but the result may be incorrectly
         * interpreted as 0.
         */
        function modExp(uint256 b, uint256 e, uint256 m) internal view returns (uint256) {
            (bool success, uint256 result) = tryModExp(b, e, m);
            if (!success) {
                Panic.panic(Panic.DIVISION_BY_ZERO);
            }
            return result;
        }
    
        /**
         * @dev Returns the modular exponentiation of the specified base, exponent and modulus (b ** e % m).
         * It includes a success flag indicating if the operation succeeded. Operation will be marked as failed if trying
         * to operate modulo 0 or if the underlying precompile reverted.
         *
         * IMPORTANT: The result is only valid if the success flag is true. When using this function, make sure the chain
         * you're using it on supports the precompiled contract for modular exponentiation at address 0x05 as specified in
         * https://eips.ethereum.org/EIPS/eip-198[EIP-198]. Otherwise, the underlying function will succeed given the lack
         * of a revert, but the result may be incorrectly interpreted as 0.
         */
        function tryModExp(uint256 b, uint256 e, uint256 m) internal view returns (bool success, uint256 result) {
            if (m == 0) return (false, 0);
            assembly ("memory-safe") {
                let ptr := mload(0x40)
                // | Offset    | Content    | Content (Hex)                                                      |
                // |-----------|------------|--------------------------------------------------------------------|
                // | 0x00:0x1f | size of b  | 0x0000000000000000000000000000000000000000000000000000000000000020 |
                // | 0x20:0x3f | size of e  | 0x0000000000000000000000000000000000000000000000000000000000000020 |
                // | 0x40:0x5f | size of m  | 0x0000000000000000000000000000000000000000000000000000000000000020 |
                // | 0x60:0x7f | value of b | 0x<.............................................................b> |
                // | 0x80:0x9f | value of e | 0x<.............................................................e> |
                // | 0xa0:0xbf | value of m | 0x<.............................................................m> |
                mstore(ptr, 0x20)
                mstore(add(ptr, 0x20), 0x20)
                mstore(add(ptr, 0x40), 0x20)
                mstore(add(ptr, 0x60), b)
                mstore(add(ptr, 0x80), e)
                mstore(add(ptr, 0xa0), m)
    
                // Given the result < m, it's guaranteed to fit in 32 bytes,
                // so we can use the memory scratch space located at offset 0.
                success := staticcall(gas(), 0x05, ptr, 0xc0, 0x00, 0x20)
                result := mload(0x00)
            }
        }
    
        /**
         * @dev Variant of {modExp} that supports inputs of arbitrary length.
         */
        function modExp(bytes memory b, bytes memory e, bytes memory m) internal view returns (bytes memory) {
            (bool success, bytes memory result) = tryModExp(b, e, m);
            if (!success) {
                Panic.panic(Panic.DIVISION_BY_ZERO);
            }
            return result;
        }
    
        /**
         * @dev Variant of {tryModExp} that supports inputs of arbitrary length.
         */
        function tryModExp(
            bytes memory b,
            bytes memory e,
            bytes memory m
        ) internal view returns (bool success, bytes memory result) {
            if (_zeroBytes(m)) return (false, new bytes(0));
    
            uint256 mLen = m.length;
    
            // Encode call args in result and move the free memory pointer
            result = abi.encodePacked(b.length, e.length, mLen, b, e, m);
    
            assembly ("memory-safe") {
                let dataPtr := add(result, 0x20)
                // Write result on top of args to avoid allocating extra memory.
                success := staticcall(gas(), 0x05, dataPtr, mload(result), dataPtr, mLen)
                // Overwrite the length.
                // result.length > returndatasize() is guaranteed because returndatasize() == m.length
                mstore(result, mLen)
                // Set the memory pointer after the returned data.
                mstore(0x40, add(dataPtr, mLen))
            }
        }
    
        /**
         * @dev Returns whether the provided byte array is zero.
         */
        function _zeroBytes(bytes memory byteArray) private pure returns (bool) {
            for (uint256 i = 0; i < byteArray.length; ++i) {
                if (byteArray[i] != 0) {
                    return false;
                }
            }
            return true;
        }
    
        /**
         * @dev Returns the square root of a number. If the number is not a perfect square, the value is rounded
         * towards zero.
         *
         * This method is based on Newton's method for computing square roots; the algorithm is restricted to only
         * using integer operations.
         */
        function sqrt(uint256 a) internal pure returns (uint256) {
            unchecked {
                // Take care of easy edge cases when a == 0 or a == 1
                if (a <= 1) {
                    return a;
                }
    
                // In this function, we use Newton's method to get a root of `f(x) := x² - a`. It involves building a
                // sequence x_n that converges toward sqrt(a). For each iteration x_n, we also define the error between
                // the current value as `ε_n = | x_n - sqrt(a) |`.
                //
                // For our first estimation, we consider `e` the smallest power of 2 which is bigger than the square root
                // of the target. (i.e. `2**(e-1) ≤ sqrt(a) < 2**e`). We know that `e ≤ 128` because `(2¹²⁸)² = 2²⁵⁶` is
                // bigger than any uint256.
                //
                // By noticing that
                // `2**(e-1) ≤ sqrt(a) < 2**e → (2**(e-1))² ≤ a < (2**e)² → 2**(2*e-2) ≤ a < 2**(2*e)`
                // we can deduce that `e - 1` is `log2(a) / 2`. We can thus compute `x_n = 2**(e-1)` using a method similar
                // to the msb function.
                uint256 aa = a;
                uint256 xn = 1;
    
                if (aa >= (1 << 128)) {
                    aa >>= 128;
                    xn <<= 64;
                }
                if (aa >= (1 << 64)) {
                    aa >>= 64;
                    xn <<= 32;
                }
                if (aa >= (1 << 32)) {
                    aa >>= 32;
                    xn <<= 16;
                }
                if (aa >= (1 << 16)) {
                    aa >>= 16;
                    xn <<= 8;
                }
                if (aa >= (1 << 8)) {
                    aa >>= 8;
                    xn <<= 4;
                }
                if (aa >= (1 << 4)) {
                    aa >>= 4;
                    xn <<= 2;
                }
                if (aa >= (1 << 2)) {
                    xn <<= 1;
                }
    
                // We now have x_n such that `x_n = 2**(e-1) ≤ sqrt(a) < 2**e = 2 * x_n`. This implies ε_n ≤ 2**(e-1).
                //
                // We can refine our estimation by noticing that the middle of that interval minimizes the error.
                // If we move x_n to equal 2**(e-1) + 2**(e-2), then we reduce the error to ε_n ≤ 2**(e-2).
                // This is going to be our x_0 (and ε_0)
                xn = (3 * xn) >> 1; // ε_0 := | x_0 - sqrt(a) | ≤ 2**(e-2)
    
                // From here, Newton's method give us:
                // x_{n+1} = (x_n + a / x_n) / 2
                //
                // One should note that:
                // x_{n+1}² - a = ((x_n + a / x_n) / 2)² - a
                //              = ((x_n² + a) / (2 * x_n))² - a
                //              = (x_n⁴ + 2 * a * x_n² + a²) / (4 * x_n²) - a
                //              = (x_n⁴ + 2 * a * x_n² + a² - 4 * a * x_n²) / (4 * x_n²)
                //              = (x_n⁴ - 2 * a * x_n² + a²) / (4 * x_n²)
                //              = (x_n² - a)² / (2 * x_n)²
                //              = ((x_n² - a) / (2 * x_n))²
                //              ≥ 0
                // Which proves that for all n ≥ 1, sqrt(a) ≤ x_n
                //
                // This gives us the proof of quadratic convergence of the sequence:
                // ε_{n+1} = | x_{n+1} - sqrt(a) |
                //         = | (x_n + a / x_n) / 2 - sqrt(a) |
                //         = | (x_n² + a - 2*x_n*sqrt(a)) / (2 * x_n) |
                //         = | (x_n - sqrt(a))² / (2 * x_n) |
                //         = | ε_n² / (2 * x_n) |
                //         = ε_n² / | (2 * x_n) |
                //
                // For the first iteration, we have a special case where x_0 is known:
                // ε_1 = ε_0² / | (2 * x_0) |
                //     ≤ (2**(e-2))² / (2 * (2**(e-1) + 2**(e-2)))
                //     ≤ 2**(2*e-4) / (3 * 2**(e-1))
                //     ≤ 2**(e-3) / 3
                //     ≤ 2**(e-3-log2(3))
                //     ≤ 2**(e-4.5)
                //
                // For the following iterations, we use the fact that, 2**(e-1) ≤ sqrt(a) ≤ x_n:
                // ε_{n+1} = ε_n² / | (2 * x_n) |
                //         ≤ (2**(e-k))² / (2 * 2**(e-1))
                //         ≤ 2**(2*e-2*k) / 2**e
                //         ≤ 2**(e-2*k)
                xn = (xn + a / xn) >> 1; // ε_1 := | x_1 - sqrt(a) | ≤ 2**(e-4.5)  -- special case, see above
                xn = (xn + a / xn) >> 1; // ε_2 := | x_2 - sqrt(a) | ≤ 2**(e-9)    -- general case with k = 4.5
                xn = (xn + a / xn) >> 1; // ε_3 := | x_3 - sqrt(a) | ≤ 2**(e-18)   -- general case with k = 9
                xn = (xn + a / xn) >> 1; // ε_4 := | x_4 - sqrt(a) | ≤ 2**(e-36)   -- general case with k = 18
                xn = (xn + a / xn) >> 1; // ε_5 := | x_5 - sqrt(a) | ≤ 2**(e-72)   -- general case with k = 36
                xn = (xn + a / xn) >> 1; // ε_6 := | x_6 - sqrt(a) | ≤ 2**(e-144)  -- general case with k = 72
    
                // Because e ≤ 128 (as discussed during the first estimation phase), we know have reached a precision
                // ε_6 ≤ 2**(e-144) < 1. Given we're operating on integers, then we can ensure that xn is now either
                // sqrt(a) or sqrt(a) + 1.
                return xn - SafeCast.toUint(xn > a / xn);
            }
        }
    
        /**
         * @dev Calculates sqrt(a), following the selected rounding direction.
         */
        function sqrt(uint256 a, Rounding rounding) internal pure returns (uint256) {
            unchecked {
                uint256 result = sqrt(a);
                return result + SafeCast.toUint(unsignedRoundsUp(rounding) && result * result < a);
            }
        }
    
        /**
         * @dev Return the log in base 2 of a positive value rounded towards zero.
         * Returns 0 if given 0.
         */
        function log2(uint256 x) internal pure returns (uint256 r) {
            // If value has upper 128 bits set, log2 result is at least 128
            r = SafeCast.toUint(x > 0xffffffffffffffffffffffffffffffff) << 7;
            // If upper 64 bits of 128-bit half set, add 64 to result
            r |= SafeCast.toUint((x >> r) > 0xffffffffffffffff) << 6;
            // If upper 32 bits of 64-bit half set, add 32 to result
            r |= SafeCast.toUint((x >> r) > 0xffffffff) << 5;
            // If upper 16 bits of 32-bit half set, add 16 to result
            r |= SafeCast.toUint((x >> r) > 0xffff) << 4;
            // If upper 8 bits of 16-bit half set, add 8 to result
            r |= SafeCast.toUint((x >> r) > 0xff) << 3;
            // If upper 4 bits of 8-bit half set, add 4 to result
            r |= SafeCast.toUint((x >> r) > 0xf) << 2;
    
            // Shifts value right by the current result and use it as an index into this lookup table:
            //
            // | x (4 bits) |  index  | table[index] = MSB position |
            // |------------|---------|-----------------------------|
            // |    0000    |    0    |        table[0] = 0         |
            // |    0001    |    1    |        table[1] = 0         |
            // |    0010    |    2    |        table[2] = 1         |
            // |    0011    |    3    |        table[3] = 1         |
            // |    0100    |    4    |        table[4] = 2         |
            // |    0101    |    5    |        table[5] = 2         |
            // |    0110    |    6    |        table[6] = 2         |
            // |    0111    |    7    |        table[7] = 2         |
            // |    1000    |    8    |        table[8] = 3         |
            // |    1001    |    9    |        table[9] = 3         |
            // |    1010    |   10    |        table[10] = 3        |
            // |    1011    |   11    |        table[11] = 3        |
            // |    1100    |   12    |        table[12] = 3        |
            // |    1101    |   13    |        table[13] = 3        |
            // |    1110    |   14    |        table[14] = 3        |
            // |    1111    |   15    |        table[15] = 3        |
            //
            // The lookup table is represented as a 32-byte value with the MSB positions for 0-15 in the last 16 bytes.
            assembly ("memory-safe") {
                r := or(r, byte(shr(r, x), 0x0000010102020202030303030303030300000000000000000000000000000000))
            }
        }
    
        /**
         * @dev Return the log in base 2, following the selected rounding direction, of a positive value.
         * Returns 0 if given 0.
         */
        function log2(uint256 value, Rounding rounding) internal pure returns (uint256) {
            unchecked {
                uint256 result = log2(value);
                return result + SafeCast.toUint(unsignedRoundsUp(rounding) && 1 << result < value);
            }
        }
    
        /**
         * @dev Return the log in base 10 of a positive value rounded towards zero.
         * Returns 0 if given 0.
         */
        function log10(uint256 value) internal pure returns (uint256) {
            uint256 result = 0;
            unchecked {
                if (value >= 10 ** 64) {
                    value /= 10 ** 64;
                    result += 64;
                }
                if (value >= 10 ** 32) {
                    value /= 10 ** 32;
                    result += 32;
                }
                if (value >= 10 ** 16) {
                    value /= 10 ** 16;
                    result += 16;
                }
                if (value >= 10 ** 8) {
                    value /= 10 ** 8;
                    result += 8;
                }
                if (value >= 10 ** 4) {
                    value /= 10 ** 4;
                    result += 4;
                }
                if (value >= 10 ** 2) {
                    value /= 10 ** 2;
                    result += 2;
                }
                if (value >= 10 ** 1) {
                    result += 1;
                }
            }
            return result;
        }
    
        /**
         * @dev Return the log in base 10, following the selected rounding direction, of a positive value.
         * Returns 0 if given 0.
         */
        function log10(uint256 value, Rounding rounding) internal pure returns (uint256) {
            unchecked {
                uint256 result = log10(value);
                return result + SafeCast.toUint(unsignedRoundsUp(rounding) && 10 ** result < value);
            }
        }
    
        /**
         * @dev Return the log in base 256 of a positive value rounded towards zero.
         * Returns 0 if given 0.
         *
         * Adding one to the result gives the number of pairs of hex symbols needed to represent `value` as a hex string.
         */
        function log256(uint256 x) internal pure returns (uint256 r) {
            // If value has upper 128 bits set, log2 result is at least 128
            r = SafeCast.toUint(x > 0xffffffffffffffffffffffffffffffff) << 7;
            // If upper 64 bits of 128-bit half set, add 64 to result
            r |= SafeCast.toUint((x >> r) > 0xffffffffffffffff) << 6;
            // If upper 32 bits of 64-bit half set, add 32 to result
            r |= SafeCast.toUint((x >> r) > 0xffffffff) << 5;
            // If upper 16 bits of 32-bit half set, add 16 to result
            r |= SafeCast.toUint((x >> r) > 0xffff) << 4;
            // Add 1 if upper 8 bits of 16-bit half set, and divide accumulated result by 8
            return (r >> 3) | SafeCast.toUint((x >> r) > 0xff);
        }
    
        /**
         * @dev Return the log in base 256, following the selected rounding direction, of a positive value.
         * Returns 0 if given 0.
         */
        function log256(uint256 value, Rounding rounding) internal pure returns (uint256) {
            unchecked {
                uint256 result = log256(value);
                return result + SafeCast.toUint(unsignedRoundsUp(rounding) && 1 << (result << 3) < value);
            }
        }
    
        /**
         * @dev Returns whether a provided rounding mode is considered rounding up for unsigned integers.
         */
        function unsignedRoundsUp(Rounding rounding) internal pure returns (bool) {
            return uint8(rounding) % 2 == 1;
        }
    }
    
    // File: @openzeppelin/contracts/utils/math/SignedMath.sol
    
    
    // OpenZeppelin Contracts (last updated v5.1.0) (utils/math/SignedMath.sol)
    
    pragma solidity ^0.8.20;
    
    
    /**
     * @dev Standard signed math utilities missing in the Solidity language.
     */
    library SignedMath {
        /**
         * @dev Branchless ternary evaluation for `a ? b : c`. Gas costs are constant.
         *
         * IMPORTANT: This function may reduce bytecode size and consume less gas when used standalone.
         * However, the compiler may optimize Solidity ternary operations (i.e. `a ? b : c`) to only compute
         * one branch when needed, making this function more expensive.
         */
        function ternary(bool condition, int256 a, int256 b) internal pure returns (int256) {
            unchecked {
                // branchless ternary works because:
                // b ^ (a ^ b) == a
                // b ^ 0 == b
                return b ^ ((a ^ b) * int256(SafeCast.toUint(condition)));
            }
        }
    
        /**
         * @dev Returns the largest of two signed numbers.
         */
        function max(int256 a, int256 b) internal pure returns (int256) {
            return ternary(a > b, a, b);
        }
    
        /**
         * @dev Returns the smallest of two signed numbers.
         */
        function min(int256 a, int256 b) internal pure returns (int256) {
            return ternary(a < b, a, b);
        }
    
        /**
         * @dev Returns the average of two signed numbers without overflow.
         * The result is rounded towards zero.
         */
        function average(int256 a, int256 b) internal pure returns (int256) {
            // Formula from the book "Hacker's Delight"
            int256 x = (a & b) + ((a ^ b) >> 1);
            return x + (int256(uint256(x) >> 255) & (a ^ b));
        }
    
        /**
         * @dev Returns the absolute unsigned value of a signed value.
         */
        function abs(int256 n) internal pure returns (uint256) {
            unchecked {
                // Formula from the "Bit Twiddling Hacks" by Sean Eron Anderson.
                // Since `n` is a signed integer, the generated bytecode will use the SAR opcode to perform the right shift,
                // taking advantage of the most significant (or "sign" bit) in two's complement representation.
                // This opcode adds new most significant bits set to the value of the previous most significant bit. As a result,
                // the mask will either be `bytes32(0)` (if n is positive) or `~bytes32(0)` (if n is negative).
                int256 mask = n >> 255;
    
                // A `bytes32(0)` mask leaves the input unchanged, while a `~bytes32(0)` mask complements it.
                return uint256((n + mask) ^ mask);
            }
        }
    }
    
    // File: @openzeppelin/contracts/utils/Strings.sol
    
    
    // OpenZeppelin Contracts (last updated v5.3.0) (utils/Strings.sol)
    
    pragma solidity ^0.8.20;
    
    
    
    
    /**
     * @dev String operations.
     */
    library Strings {
        using SafeCast for *;
    
        bytes16 private constant HEX_DIGITS = "0123456789abcdef";
        uint8 private constant ADDRESS_LENGTH = 20;
        uint256 private constant SPECIAL_CHARS_LOOKUP =
            (1 << 0x08) | // backspace
                (1 << 0x09) | // tab
                (1 << 0x0a) | // newline
                (1 << 0x0c) | // form feed
                (1 << 0x0d) | // carriage return
                (1 << 0x22) | // double quote
                (1 << 0x5c); // backslash
    
        /**
         * @dev The `value` string doesn't fit in the specified `length`.
         */
        error StringsInsufficientHexLength(uint256 value, uint256 length);
    
        /**
         * @dev The string being parsed contains characters that are not in scope of the given base.
         */
        error StringsInvalidChar();
    
        /**
         * @dev The string being parsed is not a properly formatted address.
         */
        error StringsInvalidAddressFormat();
    
        /**
         * @dev Converts a `uint256` to its ASCII `string` decimal representation.
         */
        function toString(uint256 value) internal pure returns (string memory) {
            unchecked {
                uint256 length = Math.log10(value) + 1;
                string memory buffer = new string(length);
                uint256 ptr;
                assembly ("memory-safe") {
                    ptr := add(buffer, add(32, length))
                }
                while (true) {
                    ptr--;
                    assembly ("memory-safe") {
                        mstore8(ptr, byte(mod(value, 10), HEX_DIGITS))
                    }
                    value /= 10;
                    if (value == 0) break;
                }
                return buffer;
            }
        }
    
        /**
         * @dev Converts a `int256` to its ASCII `string` decimal representation.
         */
        function toStringSigned(int256 value) internal pure returns (string memory) {
            return string.concat(value < 0 ? "-" : "", toString(SignedMath.abs(value)));
        }
    
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation.
         */
        function toHexString(uint256 value) internal pure returns (string memory) {
            unchecked {
                return toHexString(value, Math.log256(value) + 1);
            }
        }
    
        /**
         * @dev Converts a `uint256` to its ASCII `string` hexadecimal representation with fixed length.
         */
        function toHexString(uint256 value, uint256 length) internal pure returns (string memory) {
            uint256 localValue = value;
            bytes memory buffer = new bytes(2 * length + 2);
            buffer[0] = "0";
            buffer[1] = "x";
            for (uint256 i = 2 * length + 1; i > 1; --i) {
                buffer[i] = HEX_DIGITS[localValue & 0xf];
                localValue >>= 4;
            }
            if (localValue != 0) {
                revert StringsInsufficientHexLength(value, length);
            }
            return string(buffer);
        }
    
        /**
         * @dev Converts an `address` with fixed length of 20 bytes to its not checksummed ASCII `string` hexadecimal
         * representation.
         */
        function toHexString(address addr) internal pure returns (string memory) {
            return toHexString(uint256(uint160(addr)), ADDRESS_LENGTH);
        }
    
        /**
         * @dev Converts an `address` with fixed length of 20 bytes to its checksummed ASCII `string` hexadecimal
         * representation, according to EIP-55.
         */
        function toChecksumHexString(address addr) internal pure returns (string memory) {
            bytes memory buffer = bytes(toHexString(addr));
    
            // hash the hex part of buffer (skip length + 2 bytes, length 40)
            uint256 hashValue;
            assembly ("memory-safe") {
                hashValue := shr(96, keccak256(add(buffer, 0x22), 40))
            }
    
            for (uint256 i = 41; i > 1; --i) {
                // possible values for buffer[i] are 48 (0) to 57 (9) and 97 (a) to 102 (f)
                if (hashValue & 0xf > 7 && uint8(buffer[i]) > 96) {
                    // case shift by xoring with 0x20
                    buffer[i] ^= 0x20;
                }
                hashValue >>= 4;
            }
            return string(buffer);
        }
    
        /**
         * @dev Returns true if the two strings are equal.
         */
        function equal(string memory a, string memory b) internal pure returns (bool) {
            return bytes(a).length == bytes(b).length && keccak256(bytes(a)) == keccak256(bytes(b));
        }
    
        /**
         * @dev Parse a decimal string and returns the value as a `uint256`.
         *
         * Requirements:
         * - The string must be formatted as `[0-9]*`
         * - The result must fit into an `uint256` type
         */
        function parseUint(string memory input) internal pure returns (uint256) {
            return parseUint(input, 0, bytes(input).length);
        }
    
        /**
         * @dev Variant of {parseUint-string} that parses a substring of `input` located between position `begin` (included) and
         * `end` (excluded).
         *
         * Requirements:
         * - The substring must be formatted as `[0-9]*`
         * - The result must fit into an `uint256` type
         */
        function parseUint(string memory input, uint256 begin, uint256 end) internal pure returns (uint256) {
            (bool success, uint256 value) = tryParseUint(input, begin, end);
            if (!success) revert StringsInvalidChar();
            return value;
        }
    
        /**
         * @dev Variant of {parseUint-string} that returns false if the parsing fails because of an invalid character.
         *
         * NOTE: This function will revert if the result does not fit in a `uint256`.
         */
        function tryParseUint(string memory input) internal pure returns (bool success, uint256 value) {
            return _tryParseUintUncheckedBounds(input, 0, bytes(input).length);
        }
    
        /**
         * @dev Variant of {parseUint-string-uint256-uint256} that returns false if the parsing fails because of an invalid
         * character.
         *
         * NOTE: This function will revert if the result does not fit in a `uint256`.
         */
        function tryParseUint(
            string memory input,
            uint256 begin,
            uint256 end
        ) internal pure returns (bool success, uint256 value) {
            if (end > bytes(input).length || begin > end) return (false, 0);
            return _tryParseUintUncheckedBounds(input, begin, end);
        }
    
        /**
         * @dev Implementation of {tryParseUint-string-uint256-uint256} that does not check bounds. Caller should make sure that
         * `begin <= end <= input.length`. Other inputs would result in undefined behavior.
         */
        function _tryParseUintUncheckedBounds(
            string memory input,
            uint256 begin,
            uint256 end
        ) private pure returns (bool success, uint256 value) {
            bytes memory buffer = bytes(input);
    
            uint256 result = 0;
            for (uint256 i = begin; i < end; ++i) {
                uint8 chr = _tryParseChr(bytes1(_unsafeReadBytesOffset(buffer, i)));
                if (chr > 9) return (false, 0);
                result *= 10;
                result += chr;
            }
            return (true, result);
        }
    
        /**
         * @dev Parse a decimal string and returns the value as a `int256`.
         *
         * Requirements:
         * - The string must be formatted as `[-+]?[0-9]*`
         * - The result must fit in an `int256` type.
         */
        function parseInt(string memory input) internal pure returns (int256) {
            return parseInt(input, 0, bytes(input).length);
        }
    
        /**
         * @dev Variant of {parseInt-string} that parses a substring of `input` located between position `begin` (included) and
         * `end` (excluded).
         *
         * Requirements:
         * - The substring must be formatted as `[-+]?[0-9]*`
         * - The result must fit in an `int256` type.
         */
        function parseInt(string memory input, uint256 begin, uint256 end) internal pure returns (int256) {
            (bool success, int256 value) = tryParseInt(input, begin, end);
            if (!success) revert StringsInvalidChar();
            return value;
        }
    
        /**
         * @dev Variant of {parseInt-string} that returns false if the parsing fails because of an invalid character or if
         * the result does not fit in a `int256`.
         *
         * NOTE: This function will revert if the absolute value of the result does not fit in a `uint256`.
         */
        function tryParseInt(string memory input) internal pure returns (bool success, int256 value) {
            return _tryParseIntUncheckedBounds(input, 0, bytes(input).length);
        }
    
        uint256 private constant ABS_MIN_INT256 = 2 ** 255;
    
        /**
         * @dev Variant of {parseInt-string-uint256-uint256} that returns false if the parsing fails because of an invalid
         * character or if the result does not fit in a `int256`.
         *
         * NOTE: This function will revert if the absolute value of the result does not fit in a `uint256`.
         */
        function tryParseInt(
            string memory input,
            uint256 begin,
            uint256 end
        ) internal pure returns (bool success, int256 value) {
            if (end > bytes(input).length || begin > end) return (false, 0);
            return _tryParseIntUncheckedBounds(input, begin, end);
        }
    
        /**
         * @dev Implementation of {tryParseInt-string-uint256-uint256} that does not check bounds. Caller should make sure that
         * `begin <= end <= input.length`. Other inputs would result in undefined behavior.
         */
        function _tryParseIntUncheckedBounds(
            string memory input,
            uint256 begin,
            uint256 end
        ) private pure returns (bool success, int256 value) {
            bytes memory buffer = bytes(input);
    
            // Check presence of a negative sign.
            bytes1 sign = begin == end ? bytes1(0) : bytes1(_unsafeReadBytesOffset(buffer, begin)); // don't do out-of-bound (possibly unsafe) read if sub-string is empty
            bool positiveSign = sign == bytes1("+");
            bool negativeSign = sign == bytes1("-");
            uint256 offset = (positiveSign || negativeSign).toUint();
    
            (bool absSuccess, uint256 absValue) = tryParseUint(input, begin + offset, end);
    
            if (absSuccess && absValue < ABS_MIN_INT256) {
                return (true, negativeSign ? -int256(absValue) : int256(absValue));
            } else if (absSuccess && negativeSign && absValue == ABS_MIN_INT256) {
                return (true, type(int256).min);
            } else return (false, 0);
        }
    
        /**
         * @dev Parse a hexadecimal string (with or without "0x" prefix), and returns the value as a `uint256`.
         *
         * Requirements:
         * - The string must be formatted as `(0x)?[0-9a-fA-F]*`
         * - The result must fit in an `uint256` type.
         */
        function parseHexUint(string memory input) internal pure returns (uint256) {
            return parseHexUint(input, 0, bytes(input).length);
        }
    
        /**
         * @dev Variant of {parseHexUint-string} that parses a substring of `input` located between position `begin` (included) and
         * `end` (excluded).
         *
         * Requirements:
         * - The substring must be formatted as `(0x)?[0-9a-fA-F]*`
         * - The result must fit in an `uint256` type.
         */
        function parseHexUint(string memory input, uint256 begin, uint256 end) internal pure returns (uint256) {
            (bool success, uint256 value) = tryParseHexUint(input, begin, end);
            if (!success) revert StringsInvalidChar();
            return value;
        }
    
        /**
         * @dev Variant of {parseHexUint-string} that returns false if the parsing fails because of an invalid character.
         *
         * NOTE: This function will revert if the result does not fit in a `uint256`.
         */
        function tryParseHexUint(string memory input) internal pure returns (bool success, uint256 value) {
            return _tryParseHexUintUncheckedBounds(input, 0, bytes(input).length);
        }
    
        /**
         * @dev Variant of {parseHexUint-string-uint256-uint256} that returns false if the parsing fails because of an
         * invalid character.
         *
         * NOTE: This function will revert if the result does not fit in a `uint256`.
         */
        function tryParseHexUint(
            string memory input,
            uint256 begin,
            uint256 end
        ) internal pure returns (bool success, uint256 value) {
            if (end > bytes(input).length || begin > end) return (false, 0);
            return _tryParseHexUintUncheckedBounds(input, begin, end);
        }
    
        /**
         * @dev Implementation of {tryParseHexUint-string-uint256-uint256} that does not check bounds. Caller should make sure that
         * `begin <= end <= input.length`. Other inputs would result in undefined behavior.
         */
        function _tryParseHexUintUncheckedBounds(
            string memory input,
            uint256 begin,
            uint256 end
        ) private pure returns (bool success, uint256 value) {
            bytes memory buffer = bytes(input);
    
            // skip 0x prefix if present
            bool hasPrefix = (end > begin + 1) && bytes2(_unsafeReadBytesOffset(buffer, begin)) == bytes2("0x"); // don't do out-of-bound (possibly unsafe) read if sub-string is empty
            uint256 offset = hasPrefix.toUint() * 2;
    
            uint256 result = 0;
            for (uint256 i = begin + offset; i < end; ++i) {
                uint8 chr = _tryParseChr(bytes1(_unsafeReadBytesOffset(buffer, i)));
                if (chr > 15) return (false, 0);
                result *= 16;
                unchecked {
                    // Multiplying by 16 is equivalent to a shift of 4 bits (with additional overflow check).
                    // This guarantees that adding a value < 16 will not cause an overflow, hence the unchecked.
                    result += chr;
                }
            }
            return (true, result);
        }
    
        /**
         * @dev Parse a hexadecimal string (with or without "0x" prefix), and returns the value as an `address`.
         *
         * Requirements:
         * - The string must be formatted as `(0x)?[0-9a-fA-F]{40}`
         */
        function parseAddress(string memory input) internal pure returns (address) {
            return parseAddress(input, 0, bytes(input).length);
        }
    
        /**
         * @dev Variant of {parseAddress-string} that parses a substring of `input` located between position `begin` (included) and
         * `end` (excluded).
         *
         * Requirements:
         * - The substring must be formatted as `(0x)?[0-9a-fA-F]{40}`
         */
        function parseAddress(string memory input, uint256 begin, uint256 end) internal pure returns (address) {
            (bool success, address value) = tryParseAddress(input, begin, end);
            if (!success) revert StringsInvalidAddressFormat();
            return value;
        }
    
        /**
         * @dev Variant of {parseAddress-string} that returns false if the parsing fails because the input is not a properly
         * formatted address. See {parseAddress-string} requirements.
         */
        function tryParseAddress(string memory input) internal pure returns (bool success, address value) {
            return tryParseAddress(input, 0, bytes(input).length);
        }
    
        /**
         * @dev Variant of {parseAddress-string-uint256-uint256} that returns false if the parsing fails because input is not a properly
         * formatted address. See {parseAddress-string-uint256-uint256} requirements.
         */
        function tryParseAddress(
            string memory input,
            uint256 begin,
            uint256 end
        ) internal pure returns (bool success, address value) {
            if (end > bytes(input).length || begin > end) return (false, address(0));
    
            bool hasPrefix = (end > begin + 1) && bytes2(_unsafeReadBytesOffset(bytes(input), begin)) == bytes2("0x"); // don't do out-of-bound (possibly unsafe) read if sub-string is empty
            uint256 expectedLength = 40 + hasPrefix.toUint() * 2;
    
            // check that input is the correct length
            if (end - begin == expectedLength) {
                // length guarantees that this does not overflow, and value is at most type(uint160).max
                (bool s, uint256 v) = _tryParseHexUintUncheckedBounds(input, begin, end);
                return (s, address(uint160(v)));
            } else {
                return (false, address(0));
            }
        }
    
        function _tryParseChr(bytes1 chr) private pure returns (uint8) {
            uint8 value = uint8(chr);
    
            // Try to parse `chr`:
            // - Case 1: [0-9]
            // - Case 2: [a-f]
            // - Case 3: [A-F]
            // - otherwise not supported
            unchecked {
                if (value > 47 && value < 58) value -= 48;
                else if (value > 96 && value < 103) value -= 87;
                else if (value > 64 && value < 71) value -= 55;
                else return type(uint8).max;
            }
    
            return value;
        }
    
        /**
         * @dev Escape special characters in JSON strings. This can be useful to prevent JSON injection in NFT metadata.
         *
         * WARNING: This function should only be used in double quoted JSON strings. Single quotes are not escaped.
         *
         * NOTE: This function escapes all unicode characters, and not just the ones in ranges defined in section 2.5 of
         * RFC-4627 (U+0000 to U+001F, U+0022 and U+005C). ECMAScript's `JSON.parse` does recover escaped unicode
         * characters that are not in this range, but other tooling may provide different results.
         */
        function escapeJSON(string memory input) internal pure returns (string memory) {
            bytes memory buffer = bytes(input);
            bytes memory output = new bytes(2 * buffer.length); // worst case scenario
            uint256 outputLength = 0;
    
            for (uint256 i; i < buffer.length; ++i) {
                bytes1 char = bytes1(_unsafeReadBytesOffset(buffer, i));
                if (((SPECIAL_CHARS_LOOKUP & (1 << uint8(char))) != 0)) {
                    output[outputLength++] = "\\";
                    if (char == 0x08) output[outputLength++] = "b";
                    else if (char == 0x09) output[outputLength++] = "t";
                    else if (char == 0x0a) output[outputLength++] = "n";
                    else if (char == 0x0c) output[outputLength++] = "f";
                    else if (char == 0x0d) output[outputLength++] = "r";
                    else if (char == 0x5c) output[outputLength++] = "\\";
                    else if (char == 0x22) {
                        // solhint-disable-next-line quotes
                        output[outputLength++] = '"';
                    }
                } else {
                    output[outputLength++] = char;
                }
            }
            // write the actual length and deallocate unused memory
            assembly ("memory-safe") {
                mstore(output, outputLength)
                mstore(0x40, add(output, shl(5, shr(5, add(outputLength, 63)))))
            }
    
            return string(output);
        }
    
        /**
         * @dev Reads a bytes32 from a bytes array without bounds checking.
         *
         * NOTE: making this function internal would mean it could be used with memory unsafe offset, and marking the
         * assembly block as such would prevent some optimizations.
         */
        function _unsafeReadBytesOffset(bytes memory buffer, uint256 offset) private pure returns (bytes32 value) {
            // This is not memory safe in the general case, but all calls to this private function are within bounds.
            assembly ("memory-safe") {
                value := mload(add(buffer, add(0x20, offset)))
            }
        }
    }
    
    // File: @openzeppelin/contracts/utils/cryptography/ECDSA.sol
    
    
    // OpenZeppelin Contracts (last updated v5.1.0) (utils/cryptography/ECDSA.sol)
    
    pragma solidity ^0.8.20;
    
    /**
     * @dev Elliptic Curve Digital Signature Algorithm (ECDSA) operations.
     *
     * These functions can be used to verify that a message was signed by the holder
     * of the private keys of a given address.
     */
    library ECDSA {
        enum RecoverError {
            NoError,
            InvalidSignature,
            InvalidSignatureLength,
            InvalidSignatureS
        }
    
        /**
         * @dev The signature derives the `address(0)`.
         */
        error ECDSAInvalidSignature();
    
        /**
         * @dev The signature has an invalid length.
         */
        error ECDSAInvalidSignatureLength(uint256 length);
    
        /**
         * @dev The signature has an S value that is in the upper half order.
         */
        error ECDSAInvalidSignatureS(bytes32 s);
    
        /**
         * @dev Returns the address that signed a hashed message (`hash`) with `signature` or an error. This will not
         * return address(0) without also returning an error description. Errors are documented using an enum (error type)
         * and a bytes32 providing additional information about the error.
         *
         * If no error is returned, then the address can be used for verification purposes.
         *
         * The `ecrecover` EVM precompile allows for malleable (non-unique) signatures:
         * this function rejects them by requiring the `s` value to be in the lower
         * half order, and the `v` value to be either 27 or 28.
         *
         * IMPORTANT: `hash` _must_ be the result of a hash operation for the
         * verification to be secure: it is possible to craft signatures that
         * recover to arbitrary addresses for non-hashed data. A safe way to ensure
         * this is by receiving a hash of the original message (which may otherwise
         * be too long), and then calling {MessageHashUtils-toEthSignedMessageHash} on it.
         *
         * Documentation for signature generation:
         * - with https://web3js.readthedocs.io/en/v1.3.4/web3-eth-accounts.html#sign[Web3.js]
         * - with https://docs.ethers.io/v5/api/signer/#Signer-signMessage[ethers]
         */
        function tryRecover(
            bytes32 hash,
            bytes memory signature
        ) internal pure returns (address recovered, RecoverError err, bytes32 errArg) {
            if (signature.length == 65) {
                bytes32 r;
                bytes32 s;
                uint8 v;
                // ecrecover takes the signature parameters, and the only way to get them
                // currently is to use assembly.
                assembly ("memory-safe") {
                    r := mload(add(signature, 0x20))
                    s := mload(add(signature, 0x40))
                    v := byte(0, mload(add(signature, 0x60)))
                }
                return tryRecover(hash, v, r, s);
            } else {
                return (address(0), RecoverError.InvalidSignatureLength, bytes32(signature.length));
            }
        }
    
        /**
         * @dev Returns the address that signed a hashed message (`hash`) with
         * `signature`. This address can then be used for verification purposes.
         *
         * The `ecrecover` EVM precompile allows for malleable (non-unique) signatures:
         * this function rejects them by requiring the `s` value to be in the lower
         * half order, and the `v` value to be either 27 or 28.
         *
         * IMPORTANT: `hash` _must_ be the result of a hash operation for the
         * verification to be secure: it is possible to craft signatures that
         * recover to arbitrary addresses for non-hashed data. A safe way to ensure
         * this is by receiving a hash of the original message (which may otherwise
         * be too long), and then calling {MessageHashUtils-toEthSignedMessageHash} on it.
         */
        function recover(bytes32 hash, bytes memory signature) internal pure returns (address) {
            (address recovered, RecoverError error, bytes32 errorArg) = tryRecover(hash, signature);
            _throwError(error, errorArg);
            return recovered;
        }
    
        /**
         * @dev Overload of {ECDSA-tryRecover} that receives the `r` and `vs` short-signature fields separately.
         *
         * See https://eips.ethereum.org/EIPS/eip-2098[ERC-2098 short signatures]
         */
        function tryRecover(
            bytes32 hash,
            bytes32 r,
            bytes32 vs
        ) internal pure returns (address recovered, RecoverError err, bytes32 errArg) {
            unchecked {
                bytes32 s = vs & bytes32(0x7fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff);
                // We do not check for an overflow here since the shift operation results in 0 or 1.
                uint8 v = uint8((uint256(vs) >> 255) + 27);
                return tryRecover(hash, v, r, s);
            }
        }
    
        /**
         * @dev Overload of {ECDSA-recover} that receives the `r and `vs` short-signature fields separately.
         */
        function recover(bytes32 hash, bytes32 r, bytes32 vs) internal pure returns (address) {
            (address recovered, RecoverError error, bytes32 errorArg) = tryRecover(hash, r, vs);
            _throwError(error, errorArg);
            return recovered;
        }
    
        /**
         * @dev Overload of {ECDSA-tryRecover} that receives the `v`,
         * `r` and `s` signature fields separately.
         */
        function tryRecover(
            bytes32 hash,
            uint8 v,
            bytes32 r,
            bytes32 s
        ) internal pure returns (address recovered, RecoverError err, bytes32 errArg) {
            // EIP-2 still allows signature malleability for ecrecover(). Remove this possibility and make the signature
            // unique. Appendix F in the Ethereum Yellow paper (https://ethereum.github.io/yellowpaper/paper.pdf), defines
            // the valid range for s in (301): 0 < s < secp256k1n ÷ 2 + 1, and for v in (302): v ∈ {27, 28}. Most
            // signatures from current libraries generate a unique signature with an s-value in the lower half order.
            //
            // If your library generates malleable signatures, such as s-values in the upper range, calculate a new s-value
            // with 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 - s1 and flip v from 27 to 28 or
            // vice versa. If your library also generates signatures with 0/1 for v instead 27/28, add 27 to v to accept
            // these malleable signatures as well.
            if (uint256(s) > 0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0) {
                return (address(0), RecoverError.InvalidSignatureS, s);
            }
    
            // If the signature is valid (and not malleable), return the signer address
            address signer = ecrecover(hash, v, r, s);
            if (signer == address(0)) {
                return (address(0), RecoverError.InvalidSignature, bytes32(0));
            }
    
            return (signer, RecoverError.NoError, bytes32(0));
        }
    
        /**
         * @dev Overload of {ECDSA-recover} that receives the `v`,
         * `r` and `s` signature fields separately.
         */
        function recover(bytes32 hash, uint8 v, bytes32 r, bytes32 s) internal pure returns (address) {
            (address recovered, RecoverError error, bytes32 errorArg) = tryRecover(hash, v, r, s);
            _throwError(error, errorArg);
            return recovered;
        }
    
        /**
         * @dev Optionally reverts with the corresponding custom error according to the `error` argument provided.
         */
        function _throwError(RecoverError error, bytes32 errorArg) private pure {
            if (error == RecoverError.NoError) {
                return; // no error: do nothing
            } else if (error == RecoverError.InvalidSignature) {
                revert ECDSAInvalidSignature();
            } else if (error == RecoverError.InvalidSignatureLength) {
                revert ECDSAInvalidSignatureLength(uint256(errorArg));
            } else if (error == RecoverError.InvalidSignatureS) {
                revert ECDSAInvalidSignatureS(errorArg);
            }
        }
    }
    
    // File: @openzeppelin/contracts/interfaces/IERC1271.sol
    
    
    // OpenZeppelin Contracts (last updated v5.3.0) (interfaces/IERC1271.sol)
    
    pragma solidity ^0.8.20;
    
    /**
     * @dev Interface of the ERC-1271 standard signature validation method for
     * contracts as defined in https://eips.ethereum.org/EIPS/eip-1271[ERC-1271].
     */
    interface IERC1271 {
        /**
         * @dev Should return whether the signature provided is valid for the provided data
         * @param hash      Hash of the data to be signed
         * @param signature Signature byte array associated with `hash`
         */
        function isValidSignature(bytes32 hash, bytes memory signature) external view returns (bytes4 magicValue);
    }
    
    // File: @openzeppelin/contracts/utils/cryptography/SignatureChecker.sol
    
    
    // OpenZeppelin Contracts (last updated v5.1.0) (utils/cryptography/SignatureChecker.sol)
    
    pragma solidity ^0.8.20;
    
    
    
    /**
     * @dev Signature verification helper that can be used instead of `ECDSA.recover` to seamlessly support both ECDSA
     * signatures from externally owned accounts (EOAs) as well as ERC-1271 signatures from smart contract wallets like
     * Argent and Safe Wallet (previously Gnosis Safe).
     */
    library SignatureChecker {
        /**
         * @dev Checks if a signature is valid for a given signer and data hash. If the signer is a smart contract, the
         * signature is validated against that smart contract using ERC-1271, otherwise it's validated using `ECDSA.recover`.
         *
         * NOTE: Unlike ECDSA signatures, contract signatures are revocable, and the outcome of this function can thus
         * change through time. It could return true at block N and false at block N+1 (or the opposite).
         */
        function isValidSignatureNow(address signer, bytes32 hash, bytes memory signature) internal view returns (bool) {
            if (signer.code.length == 0) {
                (address recovered, ECDSA.RecoverError err, ) = ECDSA.tryRecover(hash, signature);
                return err == ECDSA.RecoverError.NoError && recovered == signer;
            } else {
                return isValidERC1271SignatureNow(signer, hash, signature);
            }
        }
    
        /**
         * @dev Checks if a signature is valid for a given signer and data hash. The signature is validated
         * against the signer smart contract using ERC-1271.
         *
         * NOTE: Unlike ECDSA signatures, contract signatures are revocable, and the outcome of this function can thus
         * change through time. It could return true at block N and false at block N+1 (or the opposite).
         */
        function isValidERC1271SignatureNow(
            address signer,
            bytes32 hash,
            bytes memory signature
        ) internal view returns (bool) {
            (bool success, bytes memory result) = signer.staticcall(
                abi.encodeCall(IERC1271.isValidSignature, (hash, signature))
            );
            return (success &&
                result.length >= 32 &&
                abi.decode(result, (bytes32)) == bytes32(IERC1271.isValidSignature.selector));
        }
    }
    
    // File: vault.sol
    
    
    pragma solidity ^0.8.0;
    
    
    
    
    
    
    
    
    contract Vault is Ownable, Pausable, ReentrancyGuard {
        using SafeERC20 for IERC20;
    
        address public signer;
        address public recipient;
    
        mapping(uint256 => bool) public used;
    
        error InvalidNonce();
        error InvalidSignature();
    
        event Deposited(address indexed account, address token, uint256 amount, uint256 timestamp);
        event Withdrawn(uint256 indexed nonce, address account, address token, uint256 amount, uint256 timestamp);
    
        constructor(address _owner, address _signer, address _recipient) Ownable(_owner) {
            signer = _signer;
            recipient = _recipient;
        }
    
        receive() external payable {
            if (msg.sender != recipient) revert();
        }
    
        function pause() public onlyOwner whenNotPaused {
            _pause();
        }
    
        function unpause() public onlyOwner whenPaused {
            _unpause();
        }
    
        function setSigner(address _signer) external onlyOwner {
            signer = _signer;
        }
    
        function setRecipient(address _recipient) external onlyOwner {
            recipient = _recipient;
        }
    
        function depositNative() external payable nonReentrant {
            if (msg.value == 0) revert();
    
            payable(recipient).transfer(msg.value);
    
            emit Deposited(msg.sender, address(0), msg.value, block.timestamp);
        }
    
        function deposit(address _token, uint256 _amount) external nonReentrant {
            IERC20(_token).safeTransferFrom(msg.sender, recipient, _amount);
    
            emit Deposited(msg.sender, _token, _amount, block.timestamp);
        }
    
        function withdraw(
            uint256 _nonce,
            address _token,
            address _account,
            uint256 _amount,
            bytes memory _signature
        ) external nonReentrant whenNotPaused {
            if (used[_nonce] == true) revert InvalidNonce();
    
            bytes memory message = abi.encode(block.chainid, _nonce, _token, _account, _amount, address(this));
            bytes32 hash = keccak256(
                abi.encodePacked("\x19Ethereum Signed Message:\n", Strings.toString(bytes(message).length), message)
            );
            if (SignatureChecker.isValidSignatureNow(signer, hash, _signature) == false) revert InvalidSignature();
    
            used[_nonce] = true;
    
            _transfer(_token, _account, _amount);
    
            emit Withdrawn(_nonce, _account, _token, _amount, block.timestamp);
        }
    
        function claim(address _token, address _to, uint256 _amount) public onlyOwner {
            _transfer(_token, _to, _amount);
        }
    
        function _transfer(address _token, address _to, uint256 _amount) internal {
            if (_token == address(0)) {
                payable(_to).transfer(_amount);
            } else {
                IERC20(_token).safeTransfer(_to, _amount);
            }
        }
    }

    File 2 of 2: IBITToken
    // SPDX-License-Identifier: GPL-3.0
    
    
    // Dependency file: @openzeppelin/contracts/proxy/Clones.sol
    
    
    pragma solidity ^0.8.0;
    
    /**
     * @dev https://eips.ethereum.org/EIPS/eip-1167[EIP 1167] is a standard for
     * deploying minimal proxy contracts, also known as "clones".
     *
     * > To simply and cheaply clone contract functionality in an immutable way, this standard specifies
     * > a minimal bytecode implementation that delegates all calls to a known, fixed address.
     *
     * The library includes functions to deploy a proxy using either `create` (traditional deployment) or `create2`
     * (salted deterministic deployment). It also includes functions to predict the addresses of clones deployed using the
     * deterministic method.
     *
     * _Available since v3.4._
     */
    library Clones {
        /**
         * @dev Deploys and returns the address of a clone that mimics the behaviour of `implementation`.
         *
         * This function uses the create opcode, which should never revert.
         */
        function clone(address implementation) internal returns (address instance) {
    
    
    
            assembly {
                let ptr := mload(0x40)
                mstore(ptr, 0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000000000000000000000)
                mstore(add(ptr, 0x14), shl(0x60, implementation))
                mstore(add(ptr, 0x28), 0x5af43d82803e903d91602b57fd5bf30000000000000000000000000000000000)
                instance := create(0, ptr, 0x37)
            }
            require(instance != address(0), "ERC1167: create failed");
    
    
    
           
        }
    
        /**
         * @dev Deploys and returns the address of a clone that mimics the behaviour of `implementation`.
         *
         * This function uses the create2 opcode and a `salt` to deterministically deploy
         * the clone. Using the same `implementation` and `salt` multiple time will revert, since
         * the clones cannot be deployed twice at the same address.
         */
        function cloneDeterministic(address implementation, bytes32 salt) internal returns (address instance) {
            assembly {
                let ptr := mload(0x40)
                mstore(ptr, 0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000000000000000000000)
                mstore(add(ptr, 0x14), shl(0x60, implementation))
                mstore(add(ptr, 0x28), 0x5af43d82803e903d91602b57fd5bf30000000000000000000000000000000000)
                instance := create2(0, ptr, 0x37, salt)
            }
            require(instance != address(0), "ERC1167: create2 failed");
        }
    
        /**
         * @dev Computes the address of a clone deployed using {Clones-cloneDeterministic}.
         */
        function predictDeterministicAddress(
            address implementation,
            bytes32 salt,
            address deployer
        ) internal pure returns (address predicted) {
            assembly {
                let ptr := mload(0x40)
                mstore(ptr, 0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000000000000000000000)
                mstore(add(ptr, 0x14), shl(0x60, implementation))
                mstore(add(ptr, 0x28), 0x5af43d82803e903d91602b57fd5bf3ff00000000000000000000000000000000)
                mstore(add(ptr, 0x38), shl(0x60, deployer))
                mstore(add(ptr, 0x4c), salt)
                mstore(add(ptr, 0x6c), keccak256(ptr, 0x37))
                predicted := keccak256(add(ptr, 0x37), 0x55)
            }
        }
    
        /**
         * @dev Computes the address of a clone deployed using {Clones-cloneDeterministic}.
         */
        function predictDeterministicAddress(address implementation, bytes32 salt)
            internal
            view
            returns (address predicted)
        {
            return predictDeterministicAddress(implementation, salt, address(this));
        }
    }
    
    
    // File: utils/SafeMath.sol
    
    pragma solidity ^0.8.0;
    
    // CAUTION
    // This version of SafeMath should only be used with Solidity 0.8 or later,
    // because it relies on the compiler's built in overflow checks.
    
    /**
     * @dev Wrappers over Solidity's arithmetic operations.
     *
     * NOTE: `SafeMath` is no longer needed starting with Solidity 0.8. The compiler
     * now has built in overflow checking.
     */
    library SafeMath {
        /**
         * @dev Returns the addition of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryAdd(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                uint256 c = a + b;
                if (c < a) return (false, 0);
                return (true, c);
            }
        }
    
        /**
         * @dev Returns the substraction of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function trySub(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                if (b > a) return (false, 0);
                return (true, a - b);
            }
        }
    
        /**
         * @dev Returns the multiplication of two unsigned integers, with an overflow flag.
         *
         * _Available since v3.4._
         */
        function tryMul(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
                // benefit is lost if 'b' is also tested.
                // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
                if (a == 0) return (true, 0);
                uint256 c = a * b;
                if (c / a != b) return (false, 0);
                return (true, c);
            }
        }
    
        /**
         * @dev Returns the division of two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryDiv(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                if (b == 0) return (false, 0);
                return (true, a / b);
            }
        }
    
        /**
         * @dev Returns the remainder of dividing two unsigned integers, with a division by zero flag.
         *
         * _Available since v3.4._
         */
        function tryMod(uint256 a, uint256 b) internal pure returns (bool, uint256) {
            unchecked {
                if (b == 0) return (false, 0);
                return (true, a % b);
            }
        }
    
        /**
         * @dev Returns the addition of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `+` operator.
         *
         * Requirements:
         *
         * - Addition cannot overflow.
         */
        function add(uint256 a, uint256 b) internal pure returns (uint256) {
            return a + b;
        }
    
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting on
         * overflow (when the result is negative).
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(uint256 a, uint256 b) internal pure returns (uint256) {
            return a - b;
        }
    
        /**
         * @dev Returns the multiplication of two unsigned integers, reverting on
         * overflow.
         *
         * Counterpart to Solidity's `*` operator.
         *
         * Requirements:
         *
         * - Multiplication cannot overflow.
         */
        function mul(uint256 a, uint256 b) internal pure returns (uint256) {
            return a * b;
        }
    
        /**
         * @dev Returns the integer division of two unsigned integers, reverting on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator.
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(uint256 a, uint256 b) internal pure returns (uint256) {
            return a / b;
        }
    
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting when dividing by zero.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(uint256 a, uint256 b) internal pure returns (uint256) {
            return a % b;
        }
    
        /**
         * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
         * overflow (when the result is negative).
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {trySub}.
         *
         * Counterpart to Solidity's `-` operator.
         *
         * Requirements:
         *
         * - Subtraction cannot overflow.
         */
        function sub(
            uint256 a,
            uint256 b,
            string memory errorMessage
        ) internal pure returns (uint256) {
            unchecked {
                require(b <= a, errorMessage);
                return a - b;
            }
        }
    
        /**
         * @dev Returns the integer division of two unsigned integers, reverting with custom message on
         * division by zero. The result is rounded towards zero.
         *
         * Counterpart to Solidity's `/` operator. Note: this function uses a
         * `revert` opcode (which leaves remaining gas untouched) while Solidity
         * uses an invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function div(
            uint256 a,
            uint256 b,
            string memory errorMessage
        ) internal pure returns (uint256) {
            unchecked {
                require(b > 0, errorMessage);
                return a / b;
            }
        }
    
        /**
         * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
         * reverting with custom message when dividing by zero.
         *
         * CAUTION: This function is deprecated because it requires allocating memory for the error
         * message unnecessarily. For custom revert reasons use {tryMod}.
         *
         * Counterpart to Solidity's `%` operator. This function uses a `revert`
         * opcode (which leaves remaining gas untouched) while Solidity uses an
         * invalid opcode to revert (consuming all remaining gas).
         *
         * Requirements:
         *
         * - The divisor cannot be zero.
         */
        function mod(
            uint256 a,
            uint256 b,
            string memory errorMessage
        ) internal pure returns (uint256) {
            unchecked {
                require(b > 0, errorMessage);
                return a % b;
            }
        }
    }
    
    // File: erc20/Context.sol
    
    // Dependency file: @openzeppelin/contracts/utils/Context.sol
    
    pragma solidity ^0.8.0;
    
    /**
     * @dev Provides information about the current execution context, including the
     * sender of the transaction and its data. While these are generally available
     * via msg.sender and msg.data, they should not be accessed in such a direct
     * manner, since when dealing with meta-transactions the account sending and
     * paying for execution may not be the actual sender (as far as an application
     * is concerned).
     *
     * This contract is only required for intermediate, library-like contracts.
     */
    abstract contract Context{
        function _msgSender() internal view virtual returns (address) {
            return msg.sender;
        }
    
        function _msgData() internal view virtual returns (bytes calldata) {
            return msg.data;
        }
    }
    // File: erc20/Ownable.sol
    
    pragma solidity ^0.8.0;
    
    
    /**
     * @dev Contract module which provides a basic access control mechanism, where
     * there is an account (an owner) that can be granted exclusive access to
     * specific functions.
     *
     * By default, the owner account will be the one that deploys the contract. This
     * can later be changed with {transferOwnership}.
     *
     * This module is used through inheritance. It will make available the modifier
     * `onlyOwner`, which can be applied to your functions to restrict their use to
     * the owner.
     */
    abstract contract Ownable is Context {
        address private _owner;
    
        event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
    
        /**
         * @dev Initializes the contract setting the deployer as the initial owner.
         */
        constructor() {
            _setOwner(_msgSender());
        }
    
        /**
         * @dev Returns the address of the current owner.
         */
        function owner() public view virtual returns (address) {
            return _owner;
        }
    
        /**
         * @dev Throws if called by any account other than the owner.
         */
        modifier onlyOwner() {
            require(owner() == _msgSender(), "Ownable: caller is not the owner");
            _;
        }
    
        /**
         * @dev Leaves the contract without owner. It will not be possible to call
         * `onlyOwner` functions anymore. Can only be called by the current owner.
         *
         * NOTE: Renouncing ownership will leave the contract without an owner,
         * thereby removing any functionality that is only available to the owner.
         */
        function renounceOwnership() public virtual onlyOwner {
            _setOwner(address(0));
        }
    
        /**
         * @dev Transfers ownership of the contract to a new account (`newOwner`).
         * Can only be called by the current owner.
         */
        function transferOwnership(address newOwner) public virtual onlyOwner {
            require(newOwner != address(0), "Ownable: new owner is the zero address");
            _setOwner(newOwner);
        }
    
        function _setOwner(address newOwner) private {
            address oldOwner = _owner;
            _owner = newOwner;
            emit OwnershipTransferred(oldOwner, newOwner);
        }
    }
    // File: erc20/IERC20.sol
    
    pragma solidity ^0.8.0;
    
    /**
     * @dev Interface of the ERC20 standard as defined in the EIP.
     */
    interface IERC20 {
        /**
         * @dev Returns the amount of tokens in existence.
         */
        function totalSupply() external view returns (uint256);
    
        /**
         * @dev Returns the amount of tokens owned by `account`.
         */
        function balanceOf(address account) external view returns (uint256);
    
        /**
         * @dev Moves `amount` tokens from the caller's account to `recipient`.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transfer(address recipient, uint256 amount) external returns (bool);
    
        /**
         * @dev Returns the remaining number of tokens that `spender` will be
         * allowed to spend on behalf of `owner` through {transferFrom}. This is
         * zero by default.
         *
         * This value changes when {approve} or {transferFrom} are called.
         */
        function allowance(address owner, address spender) external view returns (uint256);
    
        /**
         * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * IMPORTANT: Beware that changing an allowance with this method brings the risk
         * that someone may use both the old and the new allowance by unfortunate
         * transaction ordering. One possible solution to mitigate this race
         * condition is to first reduce the spender's allowance to 0 and set the
         * desired value afterwards:
         * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
         *
         * Emits an {Approval} event.
         */
        function approve(address spender, uint256 amount) external returns (bool);
    
        /**
         * @dev Moves `amount` tokens from `sender` to `recipient` using the
         * allowance mechanism. `amount` is then deducted from the caller's
         * allowance.
         *
         * Returns a boolean value indicating whether the operation succeeded.
         *
         * Emits a {Transfer} event.
         */
        function transferFrom(
            address sender,
            address recipient,
            uint256 amount
        ) external returns (bool);
    
        /**
         * @dev Emitted when `value` tokens are moved from one account (`from`) to
         * another (`to`).
         *
         * Note that `value` may be zero.
         */
        event Transfer(address indexed from, address indexed to, uint256 value);
    
        /**
         * @dev Emitted when the allowance of a `spender` for an `owner` is set by
         * a call to {approve}. `value` is the new allowance.
         */
        event Approval(address indexed owner, address indexed spender, uint256 value);
    }
    // File: erc20/IERC20Metadata.sol
    
    pragma solidity ^0.8.0;
    
    
    /**
     * @dev Interface for the optional metadata functions from the ERC20 standard.
     *
     * _Available since v4.1._
     */
    interface IERC20Metadata is IERC20 {
        /**
         * @dev Returns the name of the token.
         */
        function name() external view returns (string memory);
    
        /**
         * @dev Returns the symbol of the token.
         */
        function symbol() external view returns (string memory);
    
        /**
         * @dev Returns the decimals places of the token.
         */
        function decimals() external view returns (uint8);
    }
    
    
    // File: erc20/ERC20.sol
    
    pragma solidity ^0.8.0;
    
    
    
    
    /**
     * @dev Implementation of the {IERC20} interface.
     *
     * This implementation is agnostic to the way tokens are created. This means
     * that a supply mechanism has to be added in a derived contract using {_mint}.
     * For a generic mechanism see {ERC20PresetMinterPauser}.
     *
     * TIP: For a detailed writeup see our guide
     * https://forum.zeppelin.solutions/t/how-to-implement-erc20-supply-mechanisms/226[How
     * to implement supply mechanisms].
     *
     * We have followed general OpenZeppelin Contracts guidelines: functions revert
     * instead returning `false` on failure. This behavior is nonetheless
     * conventional and does not conflict with the expectations of ERC20
     * applications.
     *
     * Additionally, an {Approval} event is emitted on calls to {transferFrom}.
     * This allows applications to reconstruct the allowance for all accounts just
     * by listening to said events. Other implementations of the EIP may not emit
     * these events, as it isn't required by the specification.
     *
     * Finally, the non-standard {decreaseAllowance} and {increaseAllowance}
     * functions have been added to mitigate the well-known issues around setting
     * allowances. See {IERC20-approve}.
     */
    contract ERC20 is Context, IERC20, IERC20Metadata {
        mapping(address => uint256) private _balances;
    
        mapping(address => mapping(address => uint256)) private _allowances;
    
        uint256 private _totalSupply;
    
        string private _name;
        string private _symbol;
    
        /**
         * @dev Sets the values for {name} and {symbol}.
         *
         * The default value of {decimals} is 18. To select a different value for
         * {decimals} you should overload it.
         *
         * All two of these values are immutable: they can only be set once during
         * construction.
         */
        constructor(string memory name_, string memory symbol_) {
            _name = name_;
            _symbol = symbol_;
        }
    
        /**
         * @dev Returns the name of the token.
         */
        function name() public view virtual override returns (string memory) {
            return _name;
        }
    
        /**
         * @dev Returns the symbol of the token, usually a shorter version of the
         * name.
         */
        function symbol() public view virtual override returns (string memory) {
            return _symbol;
        }
    
        /**
         * @dev Returns the number of decimals used to get its user representation.
         * For example, if `decimals` equals `2`, a balance of `505` tokens should
         * be displayed to a user as `5.05` (`505 / 10 ** 2`).
         *
         * Tokens usually opt for a value of 18, imitating the relationship between
         * Ether and Wei. This is the value {ERC20} uses, unless this function is
         * overridden;
         *
         * NOTE: This information is only used for _display_ purposes: it in
         * no way affects any of the arithmetic of the contract, including
         * {IERC20-balanceOf} and {IERC20-transfer}.
         */
        function decimals() public view virtual override returns (uint8) {
            return 18;
        }
    
        /**
         * @dev See {IERC20-totalSupply}.
         */
        function totalSupply() public view virtual override returns (uint256) {
            return _totalSupply;
        }
    
        /**
         * @dev See {IERC20-balanceOf}.
         */
        function balanceOf(address account) public view virtual override returns (uint256) {
            return _balances[account];
        }
    
        /**
         * @dev See {IERC20-transfer}.
         *
         * Requirements:
         *
         * - `recipient` cannot be the zero address.
         * - the caller must have a balance of at least `amount`.
         */
        function transfer(address recipient, uint256 amount) public virtual override returns (bool) {
            _transfer(_msgSender(), recipient, amount);
            return true;
        }
    
        /**
         * @dev See {IERC20-allowance}.
         */
        function allowance(address owner, address spender) public view virtual override returns (uint256) {
            return _allowances[owner][spender];
        }
    
        /**
         * @dev See {IERC20-approve}.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         */
        function approve(address spender, uint256 amount) public virtual override returns (bool) {
            _approve(_msgSender(), spender, amount);
            return true;
        }
    
        /**
         * @dev See {IERC20-transferFrom}.
         *
         * Emits an {Approval} event indicating the updated allowance. This is not
         * required by the EIP. See the note at the beginning of {ERC20}.
         *
         * Requirements:
         *
         * - `sender` and `recipient` cannot be the zero address.
         * - `sender` must have a balance of at least `amount`.
         * - the caller must have allowance for ``sender``'s tokens of at least
         * `amount`.
         */
        function transferFrom(
            address sender,
            address recipient,
            uint256 amount
        ) public virtual override returns (bool) {
            _transfer(sender, recipient, amount);
    
            uint256 currentAllowance = _allowances[sender][_msgSender()];
            require(currentAllowance >= amount, "ERC20: transfer amount exceeds allowance");
            unchecked {
                _approve(sender, _msgSender(), currentAllowance - amount);
            }
    
            return true;
        }
    
        /**
         * @dev Atomically increases the allowance granted to `spender` by the caller.
         *
         * This is an alternative to {approve} that can be used as a mitigation for
         * problems described in {IERC20-approve}.
         *
         * Emits an {Approval} event indicating the updated allowance.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         */
        function increaseAllowance(address spender, uint256 addedValue) public virtual returns (bool) {
            _approve(_msgSender(), spender, _allowances[_msgSender()][spender] + addedValue);
            return true;
        }
    
        /**
         * @dev Atomically decreases the allowance granted to `spender` by the caller.
         *
         * This is an alternative to {approve} that can be used as a mitigation for
         * problems described in {IERC20-approve}.
         *
         * Emits an {Approval} event indicating the updated allowance.
         *
         * Requirements:
         *
         * - `spender` cannot be the zero address.
         * - `spender` must have allowance for the caller of at least
         * `subtractedValue`.
         */
        function decreaseAllowance(address spender, uint256 subtractedValue) public virtual returns (bool) {
            uint256 currentAllowance = _allowances[_msgSender()][spender];
            require(currentAllowance >= subtractedValue, "ERC20: decreased allowance below zero");
            unchecked {
                _approve(_msgSender(), spender, currentAllowance - subtractedValue);
            }
    
            return true;
        }
    
        /**
         * @dev Moves `amount` of tokens from `sender` to `recipient`.
         *
         * This internal function is equivalent to {transfer}, and can be used to
         * e.g. implement automatic token fees, slashing mechanisms, etc.
         *
         * Emits a {Transfer} event.
         *
         * Requirements:
         *
         * - `sender` cannot be the zero address.
         * - `recipient` cannot be the zero address.
         * - `sender` must have a balance of at least `amount`.
         */
        function _transfer(
            address sender,
            address recipient,
            uint256 amount
        ) internal virtual {
            require(sender != address(0), "ERC20: transfer from the zero address");
            require(recipient != address(0), "ERC20: transfer to the zero address");
    
            _beforeTokenTransfer(sender, recipient, amount);
    
            uint256 senderBalance = _balances[sender];
            require(senderBalance >= amount, "ERC20: transfer amount exceeds balance");
            unchecked {
                _balances[sender] = senderBalance - amount;
            }
            _balances[recipient] += amount;
    
            emit Transfer(sender, recipient, amount);
    
            _afterTokenTransfer(sender, recipient, amount);
        }
    
        /** @dev Creates `amount` tokens and assigns them to `account`, increasing
         * the total supply.
         *
         * Emits a {Transfer} event with `from` set to the zero address.
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         */
        function _mint(address account, uint256 amount) internal virtual {
            require(account != address(0), "ERC20: mint to the zero address");
    
            _beforeTokenTransfer(address(0), account, amount);
    
            _totalSupply += amount;
            _balances[account] += amount;
            emit Transfer(address(0), account, amount);
    
            _afterTokenTransfer(address(0), account, amount);
        }
    
        /**
         * @dev Destroys `amount` tokens from `account`, reducing the
         * total supply.
         *
         * Emits a {Transfer} event with `to` set to the zero address.
         *
         * Requirements:
         *
         * - `account` cannot be the zero address.
         * - `account` must have at least `amount` tokens.
         */
        function _burn(address account, uint256 amount) internal virtual {
            require(account != address(0), "ERC20: burn from the zero address");
    
            _beforeTokenTransfer(account, address(0), amount);
    
            uint256 accountBalance = _balances[account];
            require(accountBalance >= amount, "ERC20: burn amount exceeds balance");
            unchecked {
                _balances[account] = accountBalance - amount;
            }
            _totalSupply -= amount;
    
            emit Transfer(account, address(0), amount);
    
            _afterTokenTransfer(account, address(0), amount);
        }
    
        /**
         * @dev Sets `amount` as the allowance of `spender` over the `owner` s tokens.
         *
         * This internal function is equivalent to `approve`, and can be used to
         * e.g. set automatic allowances for certain subsystems, etc.
         *
         * Emits an {Approval} event.
         *
         * Requirements:
         *
         * - `owner` cannot be the zero address.
         * - `spender` cannot be the zero address.
         */
        function _approve(
            address owner,
            address spender,
            uint256 amount
        ) internal virtual {
            require(owner != address(0), "ERC20: approve from the zero address");
            require(spender != address(0), "ERC20: approve to the zero address");
    
            _allowances[owner][spender] = amount;
            emit Approval(owner, spender, amount);
        }
    
        /**
         * @dev Hook that is called before any transfer of tokens. This includes
         * minting and burning.
         *
         * Calling conditions:
         *
         * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
         * will be transferred to `to`.
         * - when `from` is zero, `amount` tokens will be minted for `to`.
         * - when `to` is zero, `amount` of ``from``'s tokens will be burned.
         * - `from` and `to` are never both zero.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _beforeTokenTransfer(
            address from,
            address to,
            uint256 amount
        ) internal virtual {}
    
        /**
         * @dev Hook that is called after any transfer of tokens. This includes
         * minting and burning.
         *
         * Calling conditions:
         *
         * - when `from` and `to` are both non-zero, `amount` of ``from``'s tokens
         * has been transferred to `to`.
         * - when `from` is zero, `amount` tokens have been minted for `to`.
         * - when `to` is zero, `amount` of ``from``'s tokens have been burned.
         * - `from` and `to` are never both zero.
         *
         * To learn more about hooks, head to xref:ROOT:extending-contracts.adoc#using-hooks[Using Hooks].
         */
        function _afterTokenTransfer(
            address from,
            address to,
            uint256 amount
        ) internal virtual {}
    }
    
    pragma solidity >=0.8.4;
    
    contract IBITToken is ERC20, Ownable {
        using SafeMath for uint256;
        mapping(address => bool) public blacklisted;  // 黑名单映射
    
        constructor(
            string memory name_,
            string memory symbol_,
            uint256 totalSupply_
        ) payable ERC20(name_, symbol_) {
            /*
                _mint is an internal function in ERC20.sol that is only called here,
                and CANNOT be called ever again
            */
            _mint(owner(), totalSupply_);
    
        }
    
        function addToBlacklist(address account) external onlyOwner {
            blacklisted[account] = true;
        }
    
        function removeFromBlacklist(address account) external onlyOwner {
            blacklisted[account] = false;
        }
    
        function isBlacklisted(address account) external view returns (bool) {
            return blacklisted[account];
        }
    
        receive() external payable {}
    
        function _transfer(
            address from,
            address to,
            uint256 amount
        ) internal override {
            require(!blacklisted[from], "ERC20WithBlacklist: Sender is blacklisted");
            require(!blacklisted[to], "ERC20WithBlacklist: Recipient is blacklisted");
            require(from != address(0), "ERC20: transfer from the zero address");
            
            super._transfer(from, to, amount);
            
        }
    
    }