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pragma solidity 0.7.5;
/*
    The MIT License (MIT)
    Copyright (c) 2018 Murray Software, LLC.
    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:
    The above copyright notice and this permission notice shall be included
    in all copies or substantial portions of the Software.
    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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{"ERC20Interface.sol":{"content":"// SPDX-License-Identifier: UNLICENSED\npragma solidity 0.7.5;\n\n/**\n * Contract that exposes the needed erc20 
    token functions\n */\n\nabstract contract ERC20Interface {\n  // Send _value amount of tokens to address _to\n  function transfer(address _to, 
    uint256 _value)\n    public\n    virtual\n    returns (bool success);\n\n  // Get the account balance of another account with address _owner\n  
    function balanceOf(address _owner)\n    public\n    virtual\n    view\n    returns (uint256 balance);\n}\n"},"Forwarder.sol":{"content":"// SPDX
    -License-Identifier: Apache-2.0\npragma solidity 0.7.5;\nimport \u0027./TransferHelper.sol\u0027;\nimport \u0027./ERC20Interface.sol\u0027;\n\n
    /**\n * Contract that will forward any incoming Ether to the creator of the contract\n *\n */\ncontract Forwarder {\n  // Address to which any 
    funds sent to this contract will be forwarded\n  address public parentAddress;\n  event ForwarderDeposited(address from, uint256 value, bytes data
    );\n\n  /**\n   * Initialize the contract, and sets the destination address to that of the creator\n   */\n  function init(address _parentAddress) 
    external onlyUninitialized {\n    parentAddress = _parentAddress;\n    uint256 value = address(this).balance;\n\n    if (value == 0) {\n      
    return;\n    }\n\n    (bool success, ) = parentAddress.call{ value: value }(\u0027\u0027);\n    require(success, \u0027Flush failed\u0027);\n    // 
    NOTE: since we are forwarding on initialization,\n    // we don\u0027t have the context of the original sender.\n    // We still emit an event 
    about the forwarding but set\n    // the sender to the forwarder itself\n    emit ForwarderDeposited(address(this), value, msg.data);\n  }\n\n  
    /**\n   * Modifier that will execute internal code block only if the sender is the parent address\n   */\n  modifier onlyParent {\n    require(msg
    .sender == parentAddress, \u0027Only Parent\u0027);\n    _;\n  }\n\n  /**\n   * Modifier that will execute internal code block only if the contract 
    has not been initialized yet\n   */\n  modifier onlyUninitialized {\n    require(parentAddress == address(0x0), \u0027Already initialized\u0027);\n 
       _;\n  }\n\n  /**\n   * Default function; Gets called when data is sent but does not match any other function\n   */\n  fallback() external 
    payable {\n    flush();\n  }\n\n  /**\n   * Default function; Gets called when Ether is deposited with no data, and forwards it to the parent 
    address\n   */\n  receive() external payable {\n    flush();\n  }\n\n  /**\n   * Execute a token transfer of the full balance from the forwarder 
    token to the parent address\n   * @param tokenContractAddress the address of the erc20 token contract\n   */\n  function flushTokens(address 
    tokenContractAddress) external onlyParent {\n    ERC20Interface instance = ERC20Interface(tokenContractAddress);\n    address forwarderAddress = 
    address(this);\n    uint256 forwarderBalance = instance.balanceOf(forwarderAddress);\n    if (forwarderBalance == 0) {\n      return;\n    }\n\n   
     TransferHelper.safeTransfer(\n      tokenContractAddress,\n      parentAddress,\n      forwarderBalance\n    );\n  }\n\n  /**\n   * Flush the 
    entire balance of the contract to the parent address.\n   */\n  function flush() public {\n    uint256 value = address(this).balance;\n\n    if 
    (value == 0) {\n      return;\n    }\n\n    (bool success, ) = parentAddress.call{ value: value }(\u0027\u0027);\n    require(success, \u0027Flush 
    failed\u0027);\n    emit ForwarderDeposited(msg.sender, value, msg.data);\n  }\n}\n"},"TransferHelper.sol":{"content":"// SPDX-License-Identifier: 
    Apache-2.0\n\npragma solidity \u003e=0.7.5;\n\n// helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return 
    true/false\nlibrary TransferHelper {\n    function safeApprove(\n        address token,\n        address to,\n        uint256 value\n    ) internal 
    {\n        // bytes4(keccak256(bytes(\u0027approve(address,uint256)\u0027)));\n        (bool success, bytes memory data) = token.call(abi
    .encodeWithSelector(0x095ea7b3, to, value));\n        require(\n            success \u0026\u0026 (data.length == 0 || abi.decode(data, (bool))),\n 
               \u0027TransferHelper::safeApprove: approve failed\u0027\n        );\n    }\n\n    function safeTransfer(\n        address token,\n      
      address to,\n        uint256 value\n    ) internal {\n        // bytes4(keccak256(bytes(\u0027transfer(address,uint256)\u0027)));\n        (bool 
    success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));\n        require(\n            success \u0026\u0026 (data
    .length == 0 || abi.decode(data, (bool))),\n            \u0027TransferHelper::safeTransfer: transfer failed\u0027\n        );\n    }\n\n    
    function safeTransferFrom(\n        address token,\n        address from,\n        address to,\n        uint256 value\n    ) internal {\n        // 
    bytes4(keccak256(bytes(\u0027transferFrom(address,address,uint256)\u0027)));\n        (bool success, bytes memory data) = token.call(abi
    .encodeWithSelector(0x23b872dd, from, to, value));\n        require(\n            success \u0026\u0026 (data.length == 0 || abi.decode(data, (bool
    ))),\n            \u0027TransferHelper::transferFrom: transferFrom failed\u0027\n        );\n    }\n\n    function safeTransferETH(address to, 
    uint256 value) internal {\n        (bool success, ) = to.call{value: value}(new bytes(0));\n        require(success, \u0027TransferHelper
    ::safeTransferETH: ETH transfer failed\u0027);\n    }\n}\n"},"WalletSimple.sol":{"content":"// SPDX-License-Identifier: Apache-2.0\npragma solidity 
    0.7.5;\nimport \u0027./TransferHelper.sol\u0027;\nimport \u0027./Forwarder.sol\u0027;\nimport \u0027./ERC20Interface.sol\u0027;\n\n/**\n *\n * 
    WalletSimple\n * ============\n *\n * Basic multi-signer wallet designed for use in a co-signing environment where 2 signatures are required to 
    move funds.\n * Typically used in a 2-of-3 signing configuration. Uses ecrecover to allow for 2 signatures in a single transaction.\n *\n * The 
    first signature is created on the operation hash (see Data Formats) and passed to sendMultiSig/sendMultiSigToken\n * The signer is determined by 
    verifyMultiSig().\n *\n * The second signature is created by the submitter of the transaction and determined by msg.signer.\n *\n * Data Formats\n 
    * ============\n *\n * The signature is created with ethereumjs-util.ecsign(operationHash).\n * Like the eth_sign RPC call, it packs the values as 
    a 65-byte array of [r, s, v].\n * Unlike eth_sign, the message is not prefixed.\n *\n * The operationHash the result of keccak256(prefix, toAddress
    , value, data, expireTime).\n * For ether transactions, `prefix` is \"ETHER\".\n * For token transaction, `prefix` is \"ERC20\" and `data` is the 
    tokenContractAddress.\n *\n *\n */\ncontract WalletSimple {\n  // Events\n  event Deposited(address from, uint256 value, bytes data);\n  event 
    SafeModeActivated(address msgSender);\n  event Transacted(\n    address msgSender, // Address of the sender of the message initiating the 
    transaction\n    address otherSigner, // Address of the signer (second signature) used to initiate the transaction\n    bytes32 operation, // 
    Operation hash (see Data Formats)\n    address toAddress, // The address the transaction was sent to\n    uint256 value, // Amount of Wei sent to 
    the address\n    bytes data // Data sent when invoking the transaction\n  );\n\n  event BatchTransfer(address sender, address recipient, uint256 
    value);\n  // this event shows the other signer and the operation hash that they signed\n  // specific batch transfer events are emitted in 
    Batcher\n  event BatchTransacted(\n    address msgSender, // Address of the sender of the message initiating the transaction\n    address 
    otherSigner, // Address of the signer (second signature) used to initiate the transaction\n    bytes32 operation // Operation hash (see Data 
    Formats)\n  );\n\n  // Public fields\n  mapping(address =\u003e bool) public signers; // The addresses that can co-sign transactions on the 
    wallet\n  bool public safeMode = false; // When active, wallet may only send to signer addresses\n  bool public initialized = false; // True if the 
    contract has been initialized\n\n  // Internal fields\n  uint256 private constant MAX_SEQUENCE_ID_INCREASE = 10000;\n  uint256 constant 
    SEQUENCE_ID_WINDOW_SIZE = 10;\n  uint256[SEQUENCE_ID_WINDOW_SIZE] recentSequenceIds;\n\n  /**\n   * Set up a simple multi-sig wallet by specifying 
    the signers allowed to be used on this wallet.\n   * 2 signers will be required to send a transaction from this wallet.\n   * Note: The sender is 
    NOT automatically added to the list of signers.\n   * Signers CANNOT be changed once they are set\n   *\n   * @param allowedSigners An array of 
    signers on the wallet\n   */\n  function init(address[] calldata allowedSigners) external onlyUninitialized {\n    require(allowedSigners.length == 
    3, \u0027Invalid number of signers\u0027);\n\n    for (uint8 i = 0; i \u003c allowedSigners.length; i++) {\n      require(allowedSigners[i] != 
    address(0), \u0027Invalid signer\u0027);\n      signers[allowedSigners[i]] = true;\n    }\n    initialized = true;\n  }\n\n  /**\n   * Get the 
    network identifier that signers must sign over\n   * This provides protection signatures being replayed on other chains\n   * This must be a 
    virtual function because chain-specific contracts will need\n   *    to override with their own network ids. It also can\u0027t be a field\n   *   
     to allow this contract to be used by proxy with delegatecall, which will\n   *    not pick up on state variables\n   */\n  function getNetworkId() 
    internal virtual pure returns (string memory) {\n    return \u0027ETHER\u0027;\n  }\n\n  /**\n   * Get the network identifier that signers must 
    sign over for token transfers\n   * This provides protection signatures being replayed on other chains\n   * This must be a virtual function 
    because chain-specific contracts will need\n   *    to override with their own network ids. It also can\u0027t be a field\n   *    to allow this 
    contract to be used by proxy with delegatecall, which will\n   *    not pick up on state variables\n   */\n  function getTokenNetworkId() internal 
    virtual pure returns (string memory) {\n    return \u0027ERC20\u0027;\n  }\n\n  /**\n   * Get the network identifier that signers must sign over 
    for batch transfers\n   * This provides protection signatures being replayed on other chains\n   * This must be a virtual function because chain
    -specific contracts will need\n   *    to override with their own network ids. It also can\u0027t be a field\n   *    to allow this contract to be 
    used by proxy with delegatecall, which will\n   *    not pick up on state variables\n   */\n  function getBatchNetworkId() internal virtual pure 
    returns (string memory) {\n    return \u0027ETHER-Batch\u0027;\n  }\n\n  /**\n   * Determine if an address is a signer on this wallet\n   * @param 
    signer address to check\n   * returns boolean indicating whether address is signer or not\n   */\n  function isSigner(address signer) public view 
    returns (bool) {\n    return signers[signer];\n  }\n\n  /**\n   * Modifier that will execute internal code block only if the sender is an 
    authorized signer on this wallet\n   */\n  modifier onlySigner {\n    require(isSigner(msg.sender), \u0027Non-signer in onlySigner method\u0027);\n 
       _;\n  }\n\n  /**\n   * Modifier that will execute internal code block only if the contract has not been initialized yet\n   */\n  modifier 
    onlyUninitialized {\n    require(!initialized, \u0027Contract already initialized\u0027);\n    _;\n  }\n\n  /**\n   * Gets called when a 
    transaction is received with data that does not match any other method\n   */\n  fallback() external payable {\n    if (msg.value \u003e 0) {\n    
      // Fire deposited event if we are receiving funds\n      Deposited(msg.sender, msg.value, msg.data);\n    }\n  }\n\n  /**\n   * Gets called when 
    a transaction is received with ether and no data\n   */\n  receive() external payable {\n    if (msg.value \u003e 0) {\n      // Fire deposited 
    event if we are receiving funds\n      Deposited(msg.sender, msg.value, msg.data);\n    }\n  }\n\n  /**\n   * Execute a multi-signature transaction 
    from this wallet using 2 signers: one from msg.sender and the other from ecrecover.\n   * Sequence IDs are numbers starting from 1. They are used 
    to prevent replay attacks and may not be repeated.\n   *\n   * @param toAddress the destination address to send an outgoing transaction\n   * 
    @param value the amount in Wei to be sent\n   * @param data the data to send to the toAddress when invoking the transaction\n   * @param expireTime 
    the number of seconds since 1970 for which this transaction is valid\n   * @param sequenceId the unique sequence id obtainable from 
    getNextSequenceId\n   * @param signature see Data Formats\n   */\n  function sendMultiSig(\n    address toAddress,\n    uint256 value,\n    bytes 
    calldata data,\n    uint256 expireTime,\n    uint256 sequenceId,\n    bytes calldata signature\n  ) external onlySigner {\n    // Verify the other 
    signer\n    bytes32 operationHash = keccak256(\n      abi.encodePacked(\n        getNetworkId(),\n        toAddress,\n        value,\n        data
    ,\n        expireTime,\n        sequenceId\n      )\n    );\n\n    address otherSigner = verifyMultiSig(\n      toAddress,\n      operationHash,\n 
         signature,\n      expireTime,\n      sequenceId\n    );\n\n    // Success, send the transaction\n    (bool success, ) = toAddress.call{ value: 
    value }(data);\n    require(success, \u0027Call execution failed\u0027);\n\n    emit Transacted(\n      msg.sender,\n      otherSigner,\n      
    operationHash,\n      toAddress,\n      value,\n      data\n    );\n  }\n\n  /**\n   * Execute a batched multi-signature transaction from this 
    wallet using 2 signers: one from msg.sender and the other from ecrecover.\n   * Sequence IDs are numbers starting from 1. They are used to prevent 
    replay attacks and may not be repeated.\n   * The recipients and values to send are encoded in two arrays, where for index i, recipients[i] will be 
    sent values[i].\n   *\n   * @param recipients The list of recipients to send to\n   * @param values The list of values to send to\n   * @param 
    expireTime the number of seconds since 1970 for which this transaction is valid\n   * @param sequenceId the unique sequence id obtainable from 
    getNextSequenceId\n   * @param signature see Data Formats\n   */\n  function sendMultiSigBatch(\n    address[] calldata recipients,\n    uint256[] 
    calldata values,\n    uint256 expireTime,\n    uint256 sequenceId,\n    bytes calldata signature\n  ) external onlySigner {\n    require(recipients
    .length != 0, \u0027Not enough recipients\u0027);\n    require(\n      recipients.length == values.length,\n      \u0027Unequal recipients and 
    values\u0027\n    );\n    require(recipients.length \u003c 256, \u0027Too many recipients, max 255\u0027);\n\n    // Verify the other signer\n    
    bytes32 operationHash = keccak256(\n      abi.encodePacked(\n        getBatchNetworkId(),\n        recipients,\n        values,\n        expireTime
    ,\n        sequenceId\n      )\n    );\n\n    // the first parameter (toAddress) is used to ensure transactions in safe mode only go to a signer\n 
       // if in safe mode, we should use normal sendMultiSig to recover, so this check will always fail if in safe mode\n    require(!safeMode, 
    \u0027Batch in safe mode\u0027);\n    address otherSigner = verifyMultiSig(\n      address(0x0),\n      operationHash,\n      signature,\n      
    expireTime,\n      sequenceId\n    );\n\n    batchTransfer(recipients, values);\n    emit BatchTransacted(msg.sender, otherSigner, operationHash
    );\n  }\n\n  /**\n   * Transfer funds in a batch to each of recipients\n   * @param recipients The list of recipients to send to\n   * @param 
    values The list of values to send to recipients.\n   *  The recipient with index i in recipients array will be sent values[i].\n   *  Thus, 
    recipients and values must be the same length\n   */\n  function batchTransfer(\n    address[] calldata recipients,\n    uint256[] calldata 
    values\n  ) internal {\n    for (uint256 i = 0; i \u003c recipients.length; i++) {\n      require(address(this).balance \u003e= values[i], 
    \u0027Insufficient funds\u0027);\n\n      (bool success, ) = recipients[i].call{ value: values[i] }(\u0027\u0027);\n      require(success, 
    \u0027Call failed\u0027);\n\n      emit BatchTransfer(msg.sender, recipients[i], values[i]);\n    }\n  }\n\n  /**\n   * Execute a multi-signature 
    token transfer from this wallet using 2 signers: one from msg.sender and the other from ecrecover.\n   * Sequence IDs are numbers starting from 1. 
    They are used to prevent replay attacks and may not be repeated.\n   *\n   * @param toAddress the destination address to send an outgoing 
    transaction\n   * @param value the amount in tokens to be sent\n   * @param tokenContractAddress the address of the erc20 token contract\n   * 
    @param expireTime the number of seconds since 1970 for which this transaction is valid\n   * @param sequenceId the unique sequence id obtainable 
    from getNextSequenceId\n   * @param signature see Data Formats\n   */\n  function sendMultiSigToken(\n    address toAddress,\n    uint256 value,\n 
       address tokenContractAddress,\n    uint256 expireTime,\n    uint256 sequenceId,\n    bytes calldata signature\n  ) external onlySigner {\n    // 
    Verify the other signer\n    bytes32 operationHash = keccak256(\n      abi.encodePacked(\n        getTokenNetworkId(),\n        toAddress,\n       
     value,\n        tokenContractAddress,\n        expireTime,\n        sequenceId\n      )\n    );\n\n    verifyMultiSig(toAddress, operationHash, 
    signature, expireTime, sequenceId);\n\n    TransferHelper.safeTransfer(tokenContractAddress, toAddress, value);\n  }\n\n  /**\n   * Execute a token 
    flush from one of the forwarder addresses. This transfer needs only a single signature and can be done by any signer\n   *\n   * @param 
    forwarderAddress the address of the forwarder address to flush the tokens from\n   * @param tokenContractAddress the address of the erc20 token 
    contract\n   */\n  function flushForwarderTokens(\n    address payable forwarderAddress,\n    address tokenContractAddress\n  ) external onlySigner 
    {\n    Forwarder forwarder = Forwarder(forwarderAddress);\n    forwarder.flushTokens(tokenContractAddress);\n  }\n\n  /**\n   * Do common multisig 
    verification for both eth sends and erc20token transfers\n   *\n   * @param toAddress the destination address to send an outgoing transaction\n   * 
    @param operationHash see Data Formats\n   * @param signature see Data Formats\n   * @param expireTime the number of seconds since 1970 for which 
    this transaction is valid\n   * @param sequenceId the unique sequence id obtainable from getNextSequenceId\n   * returns address that has created 
    the signature\n   */\n  function verifyMultiSig(\n    address toAddress,\n    bytes32 operationHash,\n    bytes calldata signature,\n    uint256 
    expireTime,\n    uint256 sequenceId\n  ) private returns (address) {\n    address otherSigner = recoverAddressFromSignature(operationHash, 
    signature);\n\n    // Verify if we are in safe mode. In safe mode, the wallet can only send to signers\n    require(!safeMode || isSigner(toAddress
    ), \u0027External transfer in safe mode\u0027);\n\n    // Verify that the transaction has not expired\n    require(expireTime \u003e= block
    .timestamp, \u0027Transaction expired\u0027);\n\n    // Try to insert the sequence ID. Will revert if the sequence id was invalid\n    
    tryInsertSequenceId(sequenceId);\n\n    require(isSigner(otherSigner), \u0027Invalid signer\u0027);\n\n    require(otherSigner != msg.sender, 
    \u0027Signers cannot be equal\u0027);\n\n    return otherSigner;\n  }\n\n  /**\n   * Irrevocably puts contract into safe mode. When in this mode, 
    transactions may only be sent to signing addresses.\n   */\n  function activateSafeMode() external onlySigner {\n    safeMode = true;\n    
    SafeModeActivated(msg.sender);\n  }\n\n  /**\n   * Gets signer\u0027s address using ecrecover\n   * @param operationHash see Data Formats\n   * 
    @param signature see Data Formats\n   * returns address recovered from the signature\n   */\n  function recoverAddressFromSignature(\n    bytes32 
    operationHash,\n    bytes memory signature\n  ) private pure returns (address) {\n    require(signature.length == 65, \u0027Invalid signature - 
    wrong length\u0027);\n\n    // We need to unpack the signature, which is given as an array of 65 bytes (like eth.sign)\n    bytes32 r;\n    bytes32 
    s;\n    uint8 v;\n\n    // solhint-disable-next-line\n    assembly {\n      r := mload(add(signature, 32))\n      s := mload(add(signature, 64))\n 
         v := and(mload(add(signature, 65)), 255)\n    }\n    if (v \u003c 27) {\n      v += 27; // Ethereum versions are 27 or 28 as opposed to 0 or 1 
    which is submitted by some signing libs\n    }\n\n    // protect against signature malleability\n    // S value must be in the lower half orader\n 
       // reference: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/051d340171a93a3d401aaaea46b4b62fa81e5d7c/contracts/cryptography/ECDSA
    .sol#L53\n    require(\n      uint256(s) \u003c=\n        0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,\n      \"ECDSA: 
    invalid signature \u0027s\u0027 value\"\n    );\n\n    // note that this returns 0 if the signature is invalid\n    // Since 0x0 can never be a 
    signer, when the recovered signer address\n    // is checked against our signer list, that 0x0 will cause an invalid signer failure\n    return 
    ecrecover(operationHash, v, r, s);\n  }\n\n  /**\n   * Verify that the sequence id has not been used before and inserts it. Throws if the sequence 
    ID was not accepted.\n   * We collect a window of up to 10 recent sequence ids, and allow any sequence id that is not in the window and\n   * 
    greater than the minimum element in the window.\n   * @param sequenceId to insert into array of stored ids\n   */\n  function tryInsertSequenceId
    (uint256 sequenceId) private onlySigner {\n    // Keep a pointer to the lowest value element in the window\n    uint256 lowestValueIndex = 0;\n    
    // fetch recentSequenceIds into memory for function context to avoid unnecessary sloads\n    uint256[SEQUENCE_ID_WINDOW_SIZE] memory 
    _recentSequenceIds = recentSequenceIds;\n    for (uint256 i = 0; i \u003c SEQUENCE_ID_WINDOW_SIZE; i++) {\n      require(_recentSequenceIds[i] != 
    sequenceId, \u0027Sequence ID already used\u0027);\n\n      if (_recentSequenceIds[i] \u003c _recentSequenceIds[lowestValueIndex]) {\n        
    lowestValueIndex = i;\n      }\n    }\n\n    // The sequence ID being used is lower than the lowest value in the window\n    // so we cannot accept 
    it as it may have been used before\n    require(\n      sequenceId \u003e _recentSequenceIds[lowestValueIndex],\n      \u0027Sequence ID below 
    window\u0027\n    );\n\n    // Block sequence IDs which are much higher than the lowest value\n    // This prevents people blocking the contract by 
    using very large sequence IDs quickly\n    require(\n      sequenceId \u003c=\n        (_recentSequenceIds[lowestValueIndex] + 
    MAX_SEQUENCE_ID_INCREASE),\n      \u0027Sequence ID above maximum\u0027\n    );\n\n    recentSequenceIds[lowestValueIndex] = sequenceId;\n  }\n\n  
    /**\n   * Gets the next available sequence ID for signing when using executeAndConfirm\n   * returns the sequenceId one higher than the highest 
    currently stored\n   */\n  function getNextSequenceId() public view returns (uint256) {\n    uint256 highestSequenceId = 0;\n    for (uint256 i = 0
    ; i \u003c SEQUENCE_ID_WINDOW_SIZE; i++) {\n      if (recentSequenceIds[i] \u003e highestSequenceId) {\n        highestSequenceId = 
    recentSequenceIds[i];\n      }\n    }\n    return highestSequenceId + 1;\n  }\n}\n"}}
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pragma solidity 0.7.5;
/*
    The MIT License (MIT)
    Copyright (c) 2018 Murray Software, LLC.
    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:
    The above copyright notice and this permission notice shall be included
    in all copies or substantial portions of the Software.
    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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pragma solidity 0.7.5;
/*
    The MIT License (MIT)
    Copyright (c) 2018 Murray Software, LLC.
    Permission is hereby granted, free of charge, to any person obtaining
    a copy of this software and associated documentation files (the
    "Software"), to deal in the Software without restriction, including
    without limitation the rights to use, copy, modify, merge, publish,
    distribute, sublicense, and/or sell copies of the Software, and to
    permit persons to whom the Software is furnished to do so, subject to
    the following conditions:
    The above copyright notice and this permission notice shall be included
    in all copies or substantial portions of the Software.
    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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{"ERC20Interface.sol":{"content":"// SPDX-License-Identifier: UNLICENSED\npragma solidity 0.7.5;\n\n/**\n * Contract that exposes the needed erc20 
    token functions\n */\n\nabstract contract ERC20Interface {\n  // Send _value amount of tokens to address _to\n  function transfer(address _to, 
    uint256 _value)\n    public\n    virtual\n    returns (bool success);\n\n  // Get the account balance of another account with address _owner\n  
    function balanceOf(address _owner)\n    public\n    virtual\n    view\n    returns (uint256 balance);\n}\n"},"Forwarder.sol":{"content":"// SPDX
    -License-Identifier: Apache-2.0\npragma solidity 0.7.5;\nimport \u0027./TransferHelper.sol\u0027;\nimport \u0027./ERC20Interface.sol\u0027;\n\n
    /**\n * Contract that will forward any incoming Ether to the creator of the contract\n *\n */\ncontract Forwarder {\n  // Address to which any 
    funds sent to this contract will be forwarded\n  address public parentAddress;\n  event ForwarderDeposited(address from, uint256 value, bytes data
    );\n\n  /**\n   * Initialize the contract, and sets the destination address to that of the creator\n   */\n  function init(address _parentAddress) 
    external onlyUninitialized {\n    parentAddress = _parentAddress;\n    uint256 value = address(this).balance;\n\n    if (value == 0) {\n      
    return;\n    }\n\n    (bool success, ) = parentAddress.call{ value: value }(\u0027\u0027);\n    require(success, \u0027Flush failed\u0027);\n    // 
    NOTE: since we are forwarding on initialization,\n    // we don\u0027t have the context of the original sender.\n    // We still emit an event 
    about the forwarding but set\n    // the sender to the forwarder itself\n    emit ForwarderDeposited(address(this), value, msg.data);\n  }\n\n  
    /**\n   * Modifier that will execute internal code block only if the sender is the parent address\n   */\n  modifier onlyParent {\n    require(msg
    .sender == parentAddress, \u0027Only Parent\u0027);\n    _;\n  }\n\n  /**\n   * Modifier that will execute internal code block only if the contract 
    has not been initialized yet\n   */\n  modifier onlyUninitialized {\n    require(parentAddress == address(0x0), \u0027Already initialized\u0027);\n 
       _;\n  }\n\n  /**\n   * Default function; Gets called when data is sent but does not match any other function\n   */\n  fallback() external 
    payable {\n    flush();\n  }\n\n  /**\n   * Default function; Gets called when Ether is deposited with no data, and forwards it to the parent 
    address\n   */\n  receive() external payable {\n    flush();\n  }\n\n  /**\n   * Execute a token transfer of the full balance from the forwarder 
    token to the parent address\n   * @param tokenContractAddress the address of the erc20 token contract\n   */\n  function flushTokens(address 
    tokenContractAddress) external onlyParent {\n    ERC20Interface instance = ERC20Interface(tokenContractAddress);\n    address forwarderAddress = 
    address(this);\n    uint256 forwarderBalance = instance.balanceOf(forwarderAddress);\n    if (forwarderBalance == 0) {\n      return;\n    }\n\n   
     TransferHelper.safeTransfer(\n      tokenContractAddress,\n      parentAddress,\n      forwarderBalance\n    );\n  }\n\n  /**\n   * Flush the 
    entire balance of the contract to the parent address.\n   */\n  function flush() public {\n    uint256 value = address(this).balance;\n\n    if 
    (value == 0) {\n      return;\n    }\n\n    (bool success, ) = parentAddress.call{ value: value }(\u0027\u0027);\n    require(success, \u0027Flush 
    failed\u0027);\n    emit ForwarderDeposited(msg.sender, value, msg.data);\n  }\n}\n"},"TransferHelper.sol":{"content":"// SPDX-License-Identifier: 
    Apache-2.0\n\npragma solidity \u003e=0.7.5;\n\n// helper methods for interacting with ERC20 tokens and sending ETH that do not consistently return 
    true/false\nlibrary TransferHelper {\n    function safeApprove(\n        address token,\n        address to,\n        uint256 value\n    ) internal 
    {\n        // bytes4(keccak256(bytes(\u0027approve(address,uint256)\u0027)));\n        (bool success, bytes memory data) = token.call(abi
    .encodeWithSelector(0x095ea7b3, to, value));\n        require(\n            success \u0026\u0026 (data.length == 0 || abi.decode(data, (bool))),\n 
               \u0027TransferHelper::safeApprove: approve failed\u0027\n        );\n    }\n\n    function safeTransfer(\n        address token,\n      
      address to,\n        uint256 value\n    ) internal {\n        // bytes4(keccak256(bytes(\u0027transfer(address,uint256)\u0027)));\n        (bool 
    success, bytes memory data) = token.call(abi.encodeWithSelector(0xa9059cbb, to, value));\n        require(\n            success \u0026\u0026 (data
    .length == 0 || abi.decode(data, (bool))),\n            \u0027TransferHelper::safeTransfer: transfer failed\u0027\n        );\n    }\n\n    
    function safeTransferFrom(\n        address token,\n        address from,\n        address to,\n        uint256 value\n    ) internal {\n        // 
    bytes4(keccak256(bytes(\u0027transferFrom(address,address,uint256)\u0027)));\n        (bool success, bytes memory data) = token.call(abi
    .encodeWithSelector(0x23b872dd, from, to, value));\n        require(\n            success \u0026\u0026 (data.length == 0 || abi.decode(data, (bool
    ))),\n            \u0027TransferHelper::transferFrom: transferFrom failed\u0027\n        );\n    }\n\n    function safeTransferETH(address to, 
    uint256 value) internal {\n        (bool success, ) = to.call{value: value}(new bytes(0));\n        require(success, \u0027TransferHelper
    ::safeTransferETH: ETH transfer failed\u0027);\n    }\n}\n"},"WalletSimple.sol":{"content":"// SPDX-License-Identifier: Apache-2.0\npragma solidity 
    0.7.5;\nimport \u0027./TransferHelper.sol\u0027;\nimport \u0027./Forwarder.sol\u0027;\nimport \u0027./ERC20Interface.sol\u0027;\n\n/**\n *\n * 
    WalletSimple\n * ============\n *\n * Basic multi-signer wallet designed for use in a co-signing environment where 2 signatures are required to 
    move funds.\n * Typically used in a 2-of-3 signing configuration. Uses ecrecover to allow for 2 signatures in a single transaction.\n *\n * The 
    first signature is created on the operation hash (see Data Formats) and passed to sendMultiSig/sendMultiSigToken\n * The signer is determined by 
    verifyMultiSig().\n *\n * The second signature is created by the submitter of the transaction and determined by msg.signer.\n *\n * Data Formats\n 
    * ============\n *\n * The signature is created with ethereumjs-util.ecsign(operationHash).\n * Like the eth_sign RPC call, it packs the values as 
    a 65-byte array of [r, s, v].\n * Unlike eth_sign, the message is not prefixed.\n *\n * The operationHash the result of keccak256(prefix, toAddress
    , value, data, expireTime).\n * For ether transactions, `prefix` is \"ETHER\".\n * For token transaction, `prefix` is \"ERC20\" and `data` is the 
    tokenContractAddress.\n *\n *\n */\ncontract WalletSimple {\n  // Events\n  event Deposited(address from, uint256 value, bytes data);\n  event 
    SafeModeActivated(address msgSender);\n  event Transacted(\n    address msgSender, // Address of the sender of the message initiating the 
    transaction\n    address otherSigner, // Address of the signer (second signature) used to initiate the transaction\n    bytes32 operation, // 
    Operation hash (see Data Formats)\n    address toAddress, // The address the transaction was sent to\n    uint256 value, // Amount of Wei sent to 
    the address\n    bytes data // Data sent when invoking the transaction\n  );\n\n  event BatchTransfer(address sender, address recipient, uint256 
    value);\n  // this event shows the other signer and the operation hash that they signed\n  // specific batch transfer events are emitted in 
    Batcher\n  event BatchTransacted(\n    address msgSender, // Address of the sender of the message initiating the transaction\n    address 
    otherSigner, // Address of the signer (second signature) used to initiate the transaction\n    bytes32 operation // Operation hash (see Data 
    Formats)\n  );\n\n  // Public fields\n  mapping(address =\u003e bool) public signers; // The addresses that can co-sign transactions on the 
    wallet\n  bool public safeMode = false; // When active, wallet may only send to signer addresses\n  bool public initialized = false; // True if the 
    contract has been initialized\n\n  // Internal fields\n  uint256 private constant MAX_SEQUENCE_ID_INCREASE = 10000;\n  uint256 constant 
    SEQUENCE_ID_WINDOW_SIZE = 10;\n  uint256[SEQUENCE_ID_WINDOW_SIZE] recentSequenceIds;\n\n  /**\n   * Set up a simple multi-sig wallet by specifying 
    the signers allowed to be used on this wallet.\n   * 2 signers will be required to send a transaction from this wallet.\n   * Note: The sender is 
    NOT automatically added to the list of signers.\n   * Signers CANNOT be changed once they are set\n   *\n   * @param allowedSigners An array of 
    signers on the wallet\n   */\n  function init(address[] calldata allowedSigners) external onlyUninitialized {\n    require(allowedSigners.length == 
    3, \u0027Invalid number of signers\u0027);\n\n    for (uint8 i = 0; i \u003c allowedSigners.length; i++) {\n      require(allowedSigners[i] != 
    address(0), \u0027Invalid signer\u0027);\n      signers[allowedSigners[i]] = true;\n    }\n    initialized = true;\n  }\n\n  /**\n   * Get the 
    network identifier that signers must sign over\n   * This provides protection signatures being replayed on other chains\n   * This must be a 
    virtual function because chain-specific contracts will need\n   *    to override with their own network ids. It also can\u0027t be a field\n   *   
     to allow this contract to be used by proxy with delegatecall, which will\n   *    not pick up on state variables\n   */\n  function getNetworkId() 
    internal virtual pure returns (string memory) {\n    return \u0027ETHER\u0027;\n  }\n\n  /**\n   * Get the network identifier that signers must 
    sign over for token transfers\n   * This provides protection signatures being replayed on other chains\n   * This must be a virtual function 
    because chain-specific contracts will need\n   *    to override with their own network ids. It also can\u0027t be a field\n   *    to allow this 
    contract to be used by proxy with delegatecall, which will\n   *    not pick up on state variables\n   */\n  function getTokenNetworkId() internal 
    virtual pure returns (string memory) {\n    return \u0027ERC20\u0027;\n  }\n\n  /**\n   * Get the network identifier that signers must sign over 
    for batch transfers\n   * This provides protection signatures being replayed on other chains\n   * This must be a virtual function because chain
    -specific contracts will need\n   *    to override with their own network ids. It also can\u0027t be a field\n   *    to allow this contract to be 
    used by proxy with delegatecall, which will\n   *    not pick up on state variables\n   */\n  function getBatchNetworkId() internal virtual pure 
    returns (string memory) {\n    return \u0027ETHER-Batch\u0027;\n  }\n\n  /**\n   * Determine if an address is a signer on this wallet\n   * @param 
    signer address to check\n   * returns boolean indicating whether address is signer or not\n   */\n  function isSigner(address signer) public view 
    returns (bool) {\n    return signers[signer];\n  }\n\n  /**\n   * Modifier that will execute internal code block only if the sender is an 
    authorized signer on this wallet\n   */\n  modifier onlySigner {\n    require(isSigner(msg.sender), \u0027Non-signer in onlySigner method\u0027);\n 
       _;\n  }\n\n  /**\n   * Modifier that will execute internal code block only if the contract has not been initialized yet\n   */\n  modifier 
    onlyUninitialized {\n    require(!initialized, \u0027Contract already initialized\u0027);\n    _;\n  }\n\n  /**\n   * Gets called when a 
    transaction is received with data that does not match any other method\n   */\n  fallback() external payable {\n    if (msg.value \u003e 0) {\n    
      // Fire deposited event if we are receiving funds\n      Deposited(msg.sender, msg.value, msg.data);\n    }\n  }\n\n  /**\n   * Gets called when 
    a transaction is received with ether and no data\n   */\n  receive() external payable {\n    if (msg.value \u003e 0) {\n      // Fire deposited 
    event if we are receiving funds\n      Deposited(msg.sender, msg.value, msg.data);\n    }\n  }\n\n  /**\n   * Execute a multi-signature transaction 
    from this wallet using 2 signers: one from msg.sender and the other from ecrecover.\n   * Sequence IDs are numbers starting from 1. They are used 
    to prevent replay attacks and may not be repeated.\n   *\n   * @param toAddress the destination address to send an outgoing transaction\n   * 
    @param value the amount in Wei to be sent\n   * @param data the data to send to the toAddress when invoking the transaction\n   * @param expireTime 
    the number of seconds since 1970 for which this transaction is valid\n   * @param sequenceId the unique sequence id obtainable from 
    getNextSequenceId\n   * @param signature see Data Formats\n   */\n  function sendMultiSig(\n    address toAddress,\n    uint256 value,\n    bytes 
    calldata data,\n    uint256 expireTime,\n    uint256 sequenceId,\n    bytes calldata signature\n  ) external onlySigner {\n    // Verify the other 
    signer\n    bytes32 operationHash = keccak256(\n      abi.encodePacked(\n        getNetworkId(),\n        toAddress,\n        value,\n        data
    ,\n        expireTime,\n        sequenceId\n      )\n    );\n\n    address otherSigner = verifyMultiSig(\n      toAddress,\n      operationHash,\n 
         signature,\n      expireTime,\n      sequenceId\n    );\n\n    // Success, send the transaction\n    (bool success, ) = toAddress.call{ value: 
    value }(data);\n    require(success, \u0027Call execution failed\u0027);\n\n    emit Transacted(\n      msg.sender,\n      otherSigner,\n      
    operationHash,\n      toAddress,\n      value,\n      data\n    );\n  }\n\n  /**\n   * Execute a batched multi-signature transaction from this 
    wallet using 2 signers: one from msg.sender and the other from ecrecover.\n   * Sequence IDs are numbers starting from 1. They are used to prevent 
    replay attacks and may not be repeated.\n   * The recipients and values to send are encoded in two arrays, where for index i, recipients[i] will be 
    sent values[i].\n   *\n   * @param recipients The list of recipients to send to\n   * @param values The list of values to send to\n   * @param 
    expireTime the number of seconds since 1970 for which this transaction is valid\n   * @param sequenceId the unique sequence id obtainable from 
    getNextSequenceId\n   * @param signature see Data Formats\n   */\n  function sendMultiSigBatch(\n    address[] calldata recipients,\n    uint256[] 
    calldata values,\n    uint256 expireTime,\n    uint256 sequenceId,\n    bytes calldata signature\n  ) external onlySigner {\n    require(recipients
    .length != 0, \u0027Not enough recipients\u0027);\n    require(\n      recipients.length == values.length,\n      \u0027Unequal recipients and 
    values\u0027\n    );\n    require(recipients.length \u003c 256, \u0027Too many recipients, max 255\u0027);\n\n    // Verify the other signer\n    
    bytes32 operationHash = keccak256(\n      abi.encodePacked(\n        getBatchNetworkId(),\n        recipients,\n        values,\n        expireTime
    ,\n        sequenceId\n      )\n    );\n\n    // the first parameter (toAddress) is used to ensure transactions in safe mode only go to a signer\n 
       // if in safe mode, we should use normal sendMultiSig to recover, so this check will always fail if in safe mode\n    require(!safeMode, 
    \u0027Batch in safe mode\u0027);\n    address otherSigner = verifyMultiSig(\n      address(0x0),\n      operationHash,\n      signature,\n      
    expireTime,\n      sequenceId\n    );\n\n    batchTransfer(recipients, values);\n    emit BatchTransacted(msg.sender, otherSigner, operationHash
    );\n  }\n\n  /**\n   * Transfer funds in a batch to each of recipients\n   * @param recipients The list of recipients to send to\n   * @param 
    values The list of values to send to recipients.\n   *  The recipient with index i in recipients array will be sent values[i].\n   *  Thus, 
    recipients and values must be the same length\n   */\n  function batchTransfer(\n    address[] calldata recipients,\n    uint256[] calldata 
    values\n  ) internal {\n    for (uint256 i = 0; i \u003c recipients.length; i++) {\n      require(address(this).balance \u003e= values[i], 
    \u0027Insufficient funds\u0027);\n\n      (bool success, ) = recipients[i].call{ value: values[i] }(\u0027\u0027);\n      require(success, 
    \u0027Call failed\u0027);\n\n      emit BatchTransfer(msg.sender, recipients[i], values[i]);\n    }\n  }\n\n  /**\n   * Execute a multi-signature 
    token transfer from this wallet using 2 signers: one from msg.sender and the other from ecrecover.\n   * Sequence IDs are numbers starting from 1. 
    They are used to prevent replay attacks and may not be repeated.\n   *\n   * @param toAddress the destination address to send an outgoing 
    transaction\n   * @param value the amount in tokens to be sent\n   * @param tokenContractAddress the address of the erc20 token contract\n   * 
    @param expireTime the number of seconds since 1970 for which this transaction is valid\n   * @param sequenceId the unique sequence id obtainable 
    from getNextSequenceId\n   * @param signature see Data Formats\n   */\n  function sendMultiSigToken(\n    address toAddress,\n    uint256 value,\n 
       address tokenContractAddress,\n    uint256 expireTime,\n    uint256 sequenceId,\n    bytes calldata signature\n  ) external onlySigner {\n    // 
    Verify the other signer\n    bytes32 operationHash = keccak256(\n      abi.encodePacked(\n        getTokenNetworkId(),\n        toAddress,\n       
     value,\n        tokenContractAddress,\n        expireTime,\n        sequenceId\n      )\n    );\n\n    verifyMultiSig(toAddress, operationHash, 
    signature, expireTime, sequenceId);\n\n    TransferHelper.safeTransfer(tokenContractAddress, toAddress, value);\n  }\n\n  /**\n   * Execute a token 
    flush from one of the forwarder addresses. This transfer needs only a single signature and can be done by any signer\n   *\n   * @param 
    forwarderAddress the address of the forwarder address to flush the tokens from\n   * @param tokenContractAddress the address of the erc20 token 
    contract\n   */\n  function flushForwarderTokens(\n    address payable forwarderAddress,\n    address tokenContractAddress\n  ) external onlySigner 
    {\n    Forwarder forwarder = Forwarder(forwarderAddress);\n    forwarder.flushTokens(tokenContractAddress);\n  }\n\n  /**\n   * Do common multisig 
    verification for both eth sends and erc20token transfers\n   *\n   * @param toAddress the destination address to send an outgoing transaction\n   * 
    @param operationHash see Data Formats\n   * @param signature see Data Formats\n   * @param expireTime the number of seconds since 1970 for which 
    this transaction is valid\n   * @param sequenceId the unique sequence id obtainable from getNextSequenceId\n   * returns address that has created 
    the signature\n   */\n  function verifyMultiSig(\n    address toAddress,\n    bytes32 operationHash,\n    bytes calldata signature,\n    uint256 
    expireTime,\n    uint256 sequenceId\n  ) private returns (address) {\n    address otherSigner = recoverAddressFromSignature(operationHash, 
    signature);\n\n    // Verify if we are in safe mode. In safe mode, the wallet can only send to signers\n    require(!safeMode || isSigner(toAddress
    ), \u0027External transfer in safe mode\u0027);\n\n    // Verify that the transaction has not expired\n    require(expireTime \u003e= block
    .timestamp, \u0027Transaction expired\u0027);\n\n    // Try to insert the sequence ID. Will revert if the sequence id was invalid\n    
    tryInsertSequenceId(sequenceId);\n\n    require(isSigner(otherSigner), \u0027Invalid signer\u0027);\n\n    require(otherSigner != msg.sender, 
    \u0027Signers cannot be equal\u0027);\n\n    return otherSigner;\n  }\n\n  /**\n   * Irrevocably puts contract into safe mode. When in this mode, 
    transactions may only be sent to signing addresses.\n   */\n  function activateSafeMode() external onlySigner {\n    safeMode = true;\n    
    SafeModeActivated(msg.sender);\n  }\n\n  /**\n   * Gets signer\u0027s address using ecrecover\n   * @param operationHash see Data Formats\n   * 
    @param signature see Data Formats\n   * returns address recovered from the signature\n   */\n  function recoverAddressFromSignature(\n    bytes32 
    operationHash,\n    bytes memory signature\n  ) private pure returns (address) {\n    require(signature.length == 65, \u0027Invalid signature - 
    wrong length\u0027);\n\n    // We need to unpack the signature, which is given as an array of 65 bytes (like eth.sign)\n    bytes32 r;\n    bytes32 
    s;\n    uint8 v;\n\n    // solhint-disable-next-line\n    assembly {\n      r := mload(add(signature, 32))\n      s := mload(add(signature, 64))\n 
         v := and(mload(add(signature, 65)), 255)\n    }\n    if (v \u003c 27) {\n      v += 27; // Ethereum versions are 27 or 28 as opposed to 0 or 1 
    which is submitted by some signing libs\n    }\n\n    // protect against signature malleability\n    // S value must be in the lower half orader\n 
       // reference: https://github.com/OpenZeppelin/openzeppelin-contracts/blob/051d340171a93a3d401aaaea46b4b62fa81e5d7c/contracts/cryptography/ECDSA
    .sol#L53\n    require(\n      uint256(s) \u003c=\n        0x7FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF5D576E7357A4501DDFE92F46681B20A0,\n      \"ECDSA: 
    invalid signature \u0027s\u0027 value\"\n    );\n\n    // note that this returns 0 if the signature is invalid\n    // Since 0x0 can never be a 
    signer, when the recovered signer address\n    // is checked against our signer list, that 0x0 will cause an invalid signer failure\n    return 
    ecrecover(operationHash, v, r, s);\n  }\n\n  /**\n   * Verify that the sequence id has not been used before and inserts it. Throws if the sequence 
    ID was not accepted.\n   * We collect a window of up to 10 recent sequence ids, and allow any sequence id that is not in the window and\n   * 
    greater than the minimum element in the window.\n   * @param sequenceId to insert into array of stored ids\n   */\n  function tryInsertSequenceId
    (uint256 sequenceId) private onlySigner {\n    // Keep a pointer to the lowest value element in the window\n    uint256 lowestValueIndex = 0;\n    
    // fetch recentSequenceIds into memory for function context to avoid unnecessary sloads\n    uint256[SEQUENCE_ID_WINDOW_SIZE] memory 
    _recentSequenceIds = recentSequenceIds;\n    for (uint256 i = 0; i \u003c SEQUENCE_ID_WINDOW_SIZE; i++) {\n      require(_recentSequenceIds[i] != 
    sequenceId, \u0027Sequence ID already used\u0027);\n\n      if (_recentSequenceIds[i] \u003c _recentSequenceIds[lowestValueIndex]) {\n        
    lowestValueIndex = i;\n      }\n    }\n\n    // The sequence ID being used is lower than the lowest value in the window\n    // so we cannot accept 
    it as it may have been used before\n    require(\n      sequenceId \u003e _recentSequenceIds[lowestValueIndex],\n      \u0027Sequence ID below 
    window\u0027\n    );\n\n    // Block sequence IDs which are much higher than the lowest value\n    // This prevents people blocking the contract by 
    using very large sequence IDs quickly\n    require(\n      sequenceId \u003c=\n        (_recentSequenceIds[lowestValueIndex] + 
    MAX_SEQUENCE_ID_INCREASE),\n      \u0027Sequence ID above maximum\u0027\n    );\n\n    recentSequenceIds[lowestValueIndex] = sequenceId;\n  }\n\n  
    /**\n   * Gets the next available sequence ID for signing when using executeAndConfirm\n   * returns the sequenceId one higher than the highest 
    currently stored\n   */\n  function getNextSequenceId() public view returns (uint256) {\n    uint256 highestSequenceId = 0;\n    for (uint256 i = 0
    ; i \u003c SEQUENCE_ID_WINDOW_SIZE; i++) {\n      if (recentSequenceIds[i] \u003e highestSequenceId) {\n        highestSequenceId = 
    recentSequenceIds[i];\n      }\n    }\n    return highestSequenceId + 1;\n  }\n}\n"}}
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