{
  "fileName": "SafeMath.sol",
  "contractName": "SafeMath",
  "source": "// SPDX-License-Identifier: MIT\n\npragma solidity ^0.7.0;\n\n/**\n * @dev Wrappers over Solidity's arithmetic operations with added overflow\n * checks.\n *\n * Arithmetic operations in Solidity wrap on overflow. This can easily result\n * in bugs, because programmers usually assume that an overflow raises an\n * error, which is the standard behavior in high level programming languages.\n * `SafeMath` restores this intuition by reverting the transaction when an\n * operation overflows.\n *\n * Using this library instead of the unchecked operations eliminates an entire\n * class of bugs, so it's recommended to use it always.\n */\nlibrary SafeMath {\n    /**\n     * @dev Returns the addition of two unsigned integers, reverting on\n     * overflow.\n     *\n     * Counterpart to Solidity's `+` operator.\n     *\n     * Requirements:\n     *\n     * - Addition cannot overflow.\n     */\n    function add(uint256 a, uint256 b) internal pure returns (uint256) {\n        uint256 c = a + b;\n        require(c >= a, \"SafeMath: addition overflow\");\n\n        return c;\n    }\n\n    /**\n     * @dev Returns the subtraction of two unsigned integers, reverting on\n     * overflow (when the result is negative).\n     *\n     * Counterpart to Solidity's `-` operator.\n     *\n     * Requirements:\n     *\n     * - Subtraction cannot overflow.\n     */\n    function sub(uint256 a, uint256 b) internal pure returns (uint256) {\n        return sub(a, b, \"SafeMath: subtraction overflow\");\n    }\n\n    /**\n     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on\n     * overflow (when the result is negative).\n     *\n     * Counterpart to Solidity's `-` operator.\n     *\n     * Requirements:\n     *\n     * - Subtraction cannot overflow.\n     */\n    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b <= a, errorMessage);\n        uint256 c = a - b;\n\n        return c;\n    }\n\n    /**\n     * @dev Returns the multiplication of two unsigned integers, reverting on\n     * overflow.\n     *\n     * Counterpart to Solidity's `*` operator.\n     *\n     * Requirements:\n     *\n     * - Multiplication cannot overflow.\n     */\n    function mul(uint256 a, uint256 b) internal pure returns (uint256) {\n        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the\n        // benefit is lost if 'b' is also tested.\n        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522\n        if (a == 0) {\n            return 0;\n        }\n\n        uint256 c = a * b;\n        require(c / a == b, \"SafeMath: multiplication overflow\");\n\n        return c;\n    }\n\n    /**\n     * @dev Returns the integer division of two unsigned integers. Reverts on\n     * division by zero. The result is rounded towards zero.\n     *\n     * Counterpart to Solidity's `/` operator. Note: this function uses a\n     * `revert` opcode (which leaves remaining gas untouched) while Solidity\n     * uses an invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function div(uint256 a, uint256 b) internal pure returns (uint256) {\n        return div(a, b, \"SafeMath: division by zero\");\n    }\n\n    /**\n     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on\n     * division by zero. The result is rounded towards zero.\n     *\n     * Counterpart to Solidity's `/` operator. Note: this function uses a\n     * `revert` opcode (which leaves remaining gas untouched) while Solidity\n     * uses an invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b > 0, errorMessage);\n        uint256 c = a / b;\n        // assert(a == b * c + a % b); // There is no case in which this doesn't hold\n\n        return c;\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n     * Reverts when dividing by zero.\n     *\n     * Counterpart to Solidity's `%` operator. This function uses a `revert`\n     * opcode (which leaves remaining gas untouched) while Solidity uses an\n     * invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function mod(uint256 a, uint256 b) internal pure returns (uint256) {\n        return mod(a, b, \"SafeMath: modulo by zero\");\n    }\n\n    /**\n     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n     * Reverts with custom message when dividing by zero.\n     *\n     * Counterpart to Solidity's `%` operator. This function uses a `revert`\n     * opcode (which leaves remaining gas untouched) while Solidity uses an\n     * invalid opcode to revert (consuming all remaining gas).\n     *\n     * Requirements:\n     *\n     * - The divisor cannot be zero.\n     */\n    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {\n        require(b != 0, errorMessage);\n        return a % b;\n    }\n}\n",
  "sourcePath": "contracts/math/SafeMath.sol",
  "sourceMap": "622:4578:17:-:0;;;;;;;;;;;;;;;;;;;;;;;;;",
  "deployedSourceMap": "622:4578:17:-:0;;;;;;;;",
  "abi": [],
  "ast": {
    "absolutePath": "contracts/math/SafeMath.sol",
    "exportedSymbols": {
      "SafeMath": [
        2421
      ]
    },
    "id": 2422,
    "license": "MIT",
    "nodeType": "SourceUnit",
    "nodes": [
      {
        "id": 2227,
        "literals": [
          "solidity",
          "^",
          "0.7",
          ".0"
        ],
        "nodeType": "PragmaDirective",
        "src": "33:23:17"
      },
      {
        "abstract": false,
        "baseContracts": [],
        "contractDependencies": [],
        "contractKind": "library",
        "documentation": {
          "id": 2228,
          "nodeType": "StructuredDocumentation",
          "src": "58:563:17",
          "text": " @dev Wrappers over Solidity's arithmetic operations with added overflow\n checks.\n Arithmetic operations in Solidity wrap on overflow. This can easily result\n in bugs, because programmers usually assume that an overflow raises an\n error, which is the standard behavior in high level programming languages.\n `SafeMath` restores this intuition by reverting the transaction when an\n operation overflows.\n Using this library instead of the unchecked operations eliminates an entire\n class of bugs, so it's recommended to use it always."
        },
        "fullyImplemented": true,
        "id": 2421,
        "linearizedBaseContracts": [
          2421
        ],
        "name": "SafeMath",
        "nodeType": "ContractDefinition",
        "nodes": [
          {
            "body": {
              "id": 2253,
              "nodeType": "Block",
              "src": "941:109:17",
              "statements": [
                {
                  "assignments": [
                    2239
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 2239,
                      "mutability": "mutable",
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "overrides": null,
                      "scope": 2253,
                      "src": "951:9:17",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 2238,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "951:7:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 2243,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 2242,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 2240,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 2231,
                      "src": "963:1:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "+",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 2241,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 2233,
                      "src": "967:1:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "963:5:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "951:17:17"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 2247,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 2245,
                          "name": "c",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 2239,
                          "src": "986:1:17",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": ">=",
                        "rightExpression": {
                          "argumentTypes": null,
                          "id": 2246,
                          "name": "a",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 2231,
                          "src": "991:1:17",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "src": "986:6:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206164646974696f6e206f766572666c6f77",
                        "id": 2248,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "994:29:17",
                        "subdenomination": null,
                        "typeDescriptions": {
                          "typeIdentifier": "t_stringliteral_30cc447bcc13b3e22b45cef0dd9b0b514842d836dd9b6eb384e20dedfb47723a",
                          "typeString": "literal_string \"SafeMath: addition overflow\""
                        },
                        "value": "SafeMath: addition overflow"
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        },
                        {
                          "typeIdentifier": "t_stringliteral_30cc447bcc13b3e22b45cef0dd9b0b514842d836dd9b6eb384e20dedfb47723a",
                          "typeString": "literal_string \"SafeMath: addition overflow\""
                        }
                      ],
                      "id": 2244,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        -18,
                        -18
                      ],
                      "referencedDeclaration": -18,
                      "src": "978:7:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 2249,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "978:46:17",
                    "tryCall": false,
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 2250,
                  "nodeType": "ExpressionStatement",
                  "src": "978:46:17"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 2251,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 2239,
                    "src": "1042:1:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 2237,
                  "id": 2252,
                  "nodeType": "Return",
                  "src": "1035:8:17"
                }
              ]
            },
            "documentation": {
              "id": 2229,
              "nodeType": "StructuredDocumentation",
              "src": "645:224:17",
              "text": " @dev Returns the addition of two unsigned integers, reverting on\n overflow.\n Counterpart to Solidity's `+` operator.\n Requirements:\n - Addition cannot overflow."
            },
            "id": 2254,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "add",
            "nodeType": "FunctionDefinition",
            "overrides": null,
            "parameters": {
              "id": 2234,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2231,
                  "mutability": "mutable",
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2254,
                  "src": "887:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2230,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "887:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 2233,
                  "mutability": "mutable",
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2254,
                  "src": "898:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2232,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "898:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "886:22:17"
            },
            "returnParameters": {
              "id": 2237,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2236,
                  "mutability": "mutable",
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2254,
                  "src": "932:7:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2235,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "932:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "931:9:17"
            },
            "scope": 2421,
            "src": "874:176:17",
            "stateMutability": "pure",
            "virtual": false,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 2270,
              "nodeType": "Block",
              "src": "1388:67:17",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "id": 2265,
                        "name": "a",
                        "nodeType": "Identifier",
                        "overloadedDeclarations": [],
                        "referencedDeclaration": 2257,
                        "src": "1409:1:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "id": 2266,
                        "name": "b",
                        "nodeType": "Identifier",
                        "overloadedDeclarations": [],
                        "referencedDeclaration": 2259,
                        "src": "1412:1:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a207375627472616374696f6e206f766572666c6f77",
                        "id": 2267,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "1415:32:17",
                        "subdenomination": null,
                        "typeDescriptions": {
                          "typeIdentifier": "t_stringliteral_50b058e9b5320e58880d88223c9801cd9eecdcf90323d5c2318bc1b6b916e862",
                          "typeString": "literal_string \"SafeMath: subtraction overflow\""
                        },
                        "value": "SafeMath: subtraction overflow"
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        {
                          "typeIdentifier": "t_stringliteral_50b058e9b5320e58880d88223c9801cd9eecdcf90323d5c2318bc1b6b916e862",
                          "typeString": "literal_string \"SafeMath: subtraction overflow\""
                        }
                      ],
                      "id": 2264,
                      "name": "sub",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        2271,
                        2299
                      ],
                      "referencedDeclaration": 2299,
                      "src": "1405:3:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_internal_pure$_t_uint256_$_t_uint256_$_t_string_memory_ptr_$returns$_t_uint256_$",
                        "typeString": "function (uint256,uint256,string memory) pure returns (uint256)"
                      }
                    },
                    "id": 2268,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "1405:43:17",
                    "tryCall": false,
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 2263,
                  "id": 2269,
                  "nodeType": "Return",
                  "src": "1398:50:17"
                }
              ]
            },
            "documentation": {
              "id": 2255,
              "nodeType": "StructuredDocumentation",
              "src": "1056:260:17",
              "text": " @dev Returns the subtraction of two unsigned integers, reverting on\n overflow (when the result is negative).\n Counterpart to Solidity's `-` operator.\n Requirements:\n - Subtraction cannot overflow."
            },
            "id": 2271,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "sub",
            "nodeType": "FunctionDefinition",
            "overrides": null,
            "parameters": {
              "id": 2260,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2257,
                  "mutability": "mutable",
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2271,
                  "src": "1334:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2256,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1334:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 2259,
                  "mutability": "mutable",
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2271,
                  "src": "1345:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2258,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1345:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1333:22:17"
            },
            "returnParameters": {
              "id": 2263,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2262,
                  "mutability": "mutable",
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2271,
                  "src": "1379:7:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2261,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1379:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1378:9:17"
            },
            "scope": 2421,
            "src": "1321:134:17",
            "stateMutability": "pure",
            "virtual": false,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 2298,
              "nodeType": "Block",
              "src": "1841:92:17",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 2286,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 2284,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 2276,
                          "src": "1859:1:17",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": "<=",
                        "rightExpression": {
                          "argumentTypes": null,
                          "id": 2285,
                          "name": "a",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 2274,
                          "src": "1864:1:17",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "src": "1859:6:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "id": 2287,
                        "name": "errorMessage",
                        "nodeType": "Identifier",
                        "overloadedDeclarations": [],
                        "referencedDeclaration": 2278,
                        "src": "1867:12:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_string_memory_ptr",
                          "typeString": "string memory"
                        }
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        },
                        {
                          "typeIdentifier": "t_string_memory_ptr",
                          "typeString": "string memory"
                        }
                      ],
                      "id": 2283,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        -18,
                        -18
                      ],
                      "referencedDeclaration": -18,
                      "src": "1851:7:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 2288,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "1851:29:17",
                    "tryCall": false,
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 2289,
                  "nodeType": "ExpressionStatement",
                  "src": "1851:29:17"
                },
                {
                  "assignments": [
                    2291
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 2291,
                      "mutability": "mutable",
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "overrides": null,
                      "scope": 2298,
                      "src": "1890:9:17",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 2290,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "1890:7:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 2295,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 2294,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 2292,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 2274,
                      "src": "1902:1:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "-",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 2293,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 2276,
                      "src": "1906:1:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "1902:5:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "1890:17:17"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 2296,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 2291,
                    "src": "1925:1:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 2282,
                  "id": 2297,
                  "nodeType": "Return",
                  "src": "1918:8:17"
                }
              ]
            },
            "documentation": {
              "id": 2272,
              "nodeType": "StructuredDocumentation",
              "src": "1461:280:17",
              "text": " @dev Returns the subtraction of two unsigned integers, reverting with custom message on\n overflow (when the result is negative).\n Counterpart to Solidity's `-` operator.\n Requirements:\n - Subtraction cannot overflow."
            },
            "id": 2299,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "sub",
            "nodeType": "FunctionDefinition",
            "overrides": null,
            "parameters": {
              "id": 2279,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2274,
                  "mutability": "mutable",
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2299,
                  "src": "1759:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2273,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1759:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 2276,
                  "mutability": "mutable",
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2299,
                  "src": "1770:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2275,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1770:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 2278,
                  "mutability": "mutable",
                  "name": "errorMessage",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2299,
                  "src": "1781:26:17",
                  "stateVariable": false,
                  "storageLocation": "memory",
                  "typeDescriptions": {
                    "typeIdentifier": "t_string_memory_ptr",
                    "typeString": "string"
                  },
                  "typeName": {
                    "id": 2277,
                    "name": "string",
                    "nodeType": "ElementaryTypeName",
                    "src": "1781:6:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_string_storage_ptr",
                      "typeString": "string"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1758:50:17"
            },
            "returnParameters": {
              "id": 2282,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2281,
                  "mutability": "mutable",
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2299,
                  "src": "1832:7:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2280,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1832:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1831:9:17"
            },
            "scope": 2421,
            "src": "1746:187:17",
            "stateMutability": "pure",
            "virtual": false,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 2333,
              "nodeType": "Block",
              "src": "2247:392:17",
              "statements": [
                {
                  "condition": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 2311,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 2309,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 2302,
                      "src": "2479:1:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "==",
                    "rightExpression": {
                      "argumentTypes": null,
                      "hexValue": "30",
                      "id": 2310,
                      "isConstant": false,
                      "isLValue": false,
                      "isPure": true,
                      "kind": "number",
                      "lValueRequested": false,
                      "nodeType": "Literal",
                      "src": "2484:1:17",
                      "subdenomination": null,
                      "typeDescriptions": {
                        "typeIdentifier": "t_rational_0_by_1",
                        "typeString": "int_const 0"
                      },
                      "value": "0"
                    },
                    "src": "2479:6:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_bool",
                      "typeString": "bool"
                    }
                  },
                  "falseBody": null,
                  "id": 2315,
                  "nodeType": "IfStatement",
                  "src": "2475:45:17",
                  "trueBody": {
                    "id": 2314,
                    "nodeType": "Block",
                    "src": "2487:33:17",
                    "statements": [
                      {
                        "expression": {
                          "argumentTypes": null,
                          "hexValue": "30",
                          "id": 2312,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": true,
                          "kind": "number",
                          "lValueRequested": false,
                          "nodeType": "Literal",
                          "src": "2508:1:17",
                          "subdenomination": null,
                          "typeDescriptions": {
                            "typeIdentifier": "t_rational_0_by_1",
                            "typeString": "int_const 0"
                          },
                          "value": "0"
                        },
                        "functionReturnParameters": 2308,
                        "id": 2313,
                        "nodeType": "Return",
                        "src": "2501:8:17"
                      }
                    ]
                  }
                },
                {
                  "assignments": [
                    2317
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 2317,
                      "mutability": "mutable",
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "overrides": null,
                      "scope": 2333,
                      "src": "2530:9:17",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 2316,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "2530:7:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 2321,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 2320,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 2318,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 2302,
                      "src": "2542:1:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "*",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 2319,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 2304,
                      "src": "2546:1:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "2542:5:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "2530:17:17"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 2327,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "commonType": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          },
                          "id": 2325,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": false,
                          "lValueRequested": false,
                          "leftExpression": {
                            "argumentTypes": null,
                            "id": 2323,
                            "name": "c",
                            "nodeType": "Identifier",
                            "overloadedDeclarations": [],
                            "referencedDeclaration": 2317,
                            "src": "2565:1:17",
                            "typeDescriptions": {
                              "typeIdentifier": "t_uint256",
                              "typeString": "uint256"
                            }
                          },
                          "nodeType": "BinaryOperation",
                          "operator": "/",
                          "rightExpression": {
                            "argumentTypes": null,
                            "id": 2324,
                            "name": "a",
                            "nodeType": "Identifier",
                            "overloadedDeclarations": [],
                            "referencedDeclaration": 2302,
                            "src": "2569:1:17",
                            "typeDescriptions": {
                              "typeIdentifier": "t_uint256",
                              "typeString": "uint256"
                            }
                          },
                          "src": "2565:5:17",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": "==",
                        "rightExpression": {
                          "argumentTypes": null,
                          "id": 2326,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 2304,
                          "src": "2574:1:17",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "src": "2565:10:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206d756c7469706c69636174696f6e206f766572666c6f77",
                        "id": 2328,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "2577:35:17",
                        "subdenomination": null,
                        "typeDescriptions": {
                          "typeIdentifier": "t_stringliteral_9113bb53c2876a3805b2c9242029423fc540a728243ce887ab24c82cf119fba3",
                          "typeString": "literal_string \"SafeMath: multiplication overflow\""
                        },
                        "value": "SafeMath: multiplication overflow"
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        },
                        {
                          "typeIdentifier": "t_stringliteral_9113bb53c2876a3805b2c9242029423fc540a728243ce887ab24c82cf119fba3",
                          "typeString": "literal_string \"SafeMath: multiplication overflow\""
                        }
                      ],
                      "id": 2322,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        -18,
                        -18
                      ],
                      "referencedDeclaration": -18,
                      "src": "2557:7:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 2329,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "2557:56:17",
                    "tryCall": false,
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 2330,
                  "nodeType": "ExpressionStatement",
                  "src": "2557:56:17"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 2331,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 2317,
                    "src": "2631:1:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 2308,
                  "id": 2332,
                  "nodeType": "Return",
                  "src": "2624:8:17"
                }
              ]
            },
            "documentation": {
              "id": 2300,
              "nodeType": "StructuredDocumentation",
              "src": "1939:236:17",
              "text": " @dev Returns the multiplication of two unsigned integers, reverting on\n overflow.\n Counterpart to Solidity's `*` operator.\n Requirements:\n - Multiplication cannot overflow."
            },
            "id": 2334,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "mul",
            "nodeType": "FunctionDefinition",
            "overrides": null,
            "parameters": {
              "id": 2305,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2302,
                  "mutability": "mutable",
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2334,
                  "src": "2193:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2301,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "2193:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 2304,
                  "mutability": "mutable",
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2334,
                  "src": "2204:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2303,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "2204:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "2192:22:17"
            },
            "returnParameters": {
              "id": 2308,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2307,
                  "mutability": "mutable",
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2334,
                  "src": "2238:7:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2306,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "2238:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "2237:9:17"
            },
            "scope": 2421,
            "src": "2180:459:17",
            "stateMutability": "pure",
            "virtual": false,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 2350,
              "nodeType": "Block",
              "src": "3168:63:17",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "id": 2345,
                        "name": "a",
                        "nodeType": "Identifier",
                        "overloadedDeclarations": [],
                        "referencedDeclaration": 2337,
                        "src": "3189:1:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "id": 2346,
                        "name": "b",
                        "nodeType": "Identifier",
                        "overloadedDeclarations": [],
                        "referencedDeclaration": 2339,
                        "src": "3192:1:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206469766973696f6e206279207a65726f",
                        "id": 2347,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "3195:28:17",
                        "subdenomination": null,
                        "typeDescriptions": {
                          "typeIdentifier": "t_stringliteral_5b7cc70dda4dc2143e5adb63bd5d1f349504f461dbdfd9bc76fac1f8ca6d019f",
                          "typeString": "literal_string \"SafeMath: division by zero\""
                        },
                        "value": "SafeMath: division by zero"
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        {
                          "typeIdentifier": "t_stringliteral_5b7cc70dda4dc2143e5adb63bd5d1f349504f461dbdfd9bc76fac1f8ca6d019f",
                          "typeString": "literal_string \"SafeMath: division by zero\""
                        }
                      ],
                      "id": 2344,
                      "name": "div",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        2351,
                        2379
                      ],
                      "referencedDeclaration": 2379,
                      "src": "3185:3:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_internal_pure$_t_uint256_$_t_uint256_$_t_string_memory_ptr_$returns$_t_uint256_$",
                        "typeString": "function (uint256,uint256,string memory) pure returns (uint256)"
                      }
                    },
                    "id": 2348,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "3185:39:17",
                    "tryCall": false,
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 2343,
                  "id": 2349,
                  "nodeType": "Return",
                  "src": "3178:46:17"
                }
              ]
            },
            "documentation": {
              "id": 2335,
              "nodeType": "StructuredDocumentation",
              "src": "2645:451:17",
              "text": " @dev Returns the integer division of two unsigned integers. Reverts on\n division by zero. The result is rounded towards zero.\n Counterpart to Solidity's `/` operator. Note: this function uses a\n `revert` opcode (which leaves remaining gas untouched) while Solidity\n uses an invalid opcode to revert (consuming all remaining gas).\n Requirements:\n - The divisor cannot be zero."
            },
            "id": 2351,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "div",
            "nodeType": "FunctionDefinition",
            "overrides": null,
            "parameters": {
              "id": 2340,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2337,
                  "mutability": "mutable",
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2351,
                  "src": "3114:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2336,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3114:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 2339,
                  "mutability": "mutable",
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2351,
                  "src": "3125:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2338,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3125:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "3113:22:17"
            },
            "returnParameters": {
              "id": 2343,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2342,
                  "mutability": "mutable",
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2351,
                  "src": "3159:7:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2341,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3159:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "3158:9:17"
            },
            "scope": 2421,
            "src": "3101:130:17",
            "stateMutability": "pure",
            "virtual": false,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 2378,
              "nodeType": "Block",
              "src": "3808:177:17",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 2366,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 2364,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 2356,
                          "src": "3826:1:17",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": ">",
                        "rightExpression": {
                          "argumentTypes": null,
                          "hexValue": "30",
                          "id": 2365,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": true,
                          "kind": "number",
                          "lValueRequested": false,
                          "nodeType": "Literal",
                          "src": "3830:1:17",
                          "subdenomination": null,
                          "typeDescriptions": {
                            "typeIdentifier": "t_rational_0_by_1",
                            "typeString": "int_const 0"
                          },
                          "value": "0"
                        },
                        "src": "3826:5:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "id": 2367,
                        "name": "errorMessage",
                        "nodeType": "Identifier",
                        "overloadedDeclarations": [],
                        "referencedDeclaration": 2358,
                        "src": "3833:12:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_string_memory_ptr",
                          "typeString": "string memory"
                        }
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        },
                        {
                          "typeIdentifier": "t_string_memory_ptr",
                          "typeString": "string memory"
                        }
                      ],
                      "id": 2363,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        -18,
                        -18
                      ],
                      "referencedDeclaration": -18,
                      "src": "3818:7:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 2368,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "3818:28:17",
                    "tryCall": false,
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 2369,
                  "nodeType": "ExpressionStatement",
                  "src": "3818:28:17"
                },
                {
                  "assignments": [
                    2371
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 2371,
                      "mutability": "mutable",
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "overrides": null,
                      "scope": 2378,
                      "src": "3856:9:17",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 2370,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "3856:7:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 2375,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 2374,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 2372,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 2354,
                      "src": "3868:1:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "/",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 2373,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 2356,
                      "src": "3872:1:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "3868:5:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "3856:17:17"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 2376,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 2371,
                    "src": "3977:1:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 2362,
                  "id": 2377,
                  "nodeType": "Return",
                  "src": "3970:8:17"
                }
              ]
            },
            "documentation": {
              "id": 2352,
              "nodeType": "StructuredDocumentation",
              "src": "3237:471:17",
              "text": " @dev Returns the integer division of two unsigned integers. Reverts with custom message on\n division by zero. The result is rounded towards zero.\n Counterpart to Solidity's `/` operator. Note: this function uses a\n `revert` opcode (which leaves remaining gas untouched) while Solidity\n uses an invalid opcode to revert (consuming all remaining gas).\n Requirements:\n - The divisor cannot be zero."
            },
            "id": 2379,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "div",
            "nodeType": "FunctionDefinition",
            "overrides": null,
            "parameters": {
              "id": 2359,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2354,
                  "mutability": "mutable",
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2379,
                  "src": "3726:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2353,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3726:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 2356,
                  "mutability": "mutable",
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2379,
                  "src": "3737:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2355,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3737:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 2358,
                  "mutability": "mutable",
                  "name": "errorMessage",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2379,
                  "src": "3748:26:17",
                  "stateVariable": false,
                  "storageLocation": "memory",
                  "typeDescriptions": {
                    "typeIdentifier": "t_string_memory_ptr",
                    "typeString": "string"
                  },
                  "typeName": {
                    "id": 2357,
                    "name": "string",
                    "nodeType": "ElementaryTypeName",
                    "src": "3748:6:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_string_storage_ptr",
                      "typeString": "string"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "3725:50:17"
            },
            "returnParameters": {
              "id": 2362,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2361,
                  "mutability": "mutable",
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2379,
                  "src": "3799:7:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2360,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3799:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "3798:9:17"
            },
            "scope": 2421,
            "src": "3713:272:17",
            "stateMutability": "pure",
            "virtual": false,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 2395,
              "nodeType": "Block",
              "src": "4503:61:17",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "id": 2390,
                        "name": "a",
                        "nodeType": "Identifier",
                        "overloadedDeclarations": [],
                        "referencedDeclaration": 2382,
                        "src": "4524:1:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "id": 2391,
                        "name": "b",
                        "nodeType": "Identifier",
                        "overloadedDeclarations": [],
                        "referencedDeclaration": 2384,
                        "src": "4527:1:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206d6f64756c6f206279207a65726f",
                        "id": 2392,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "4530:26:17",
                        "subdenomination": null,
                        "typeDescriptions": {
                          "typeIdentifier": "t_stringliteral_726e51f7b81fce0a68f5f214f445e275313b20b1633f08ce954ee39abf8d7832",
                          "typeString": "literal_string \"SafeMath: modulo by zero\""
                        },
                        "value": "SafeMath: modulo by zero"
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        {
                          "typeIdentifier": "t_stringliteral_726e51f7b81fce0a68f5f214f445e275313b20b1633f08ce954ee39abf8d7832",
                          "typeString": "literal_string \"SafeMath: modulo by zero\""
                        }
                      ],
                      "id": 2389,
                      "name": "mod",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        2396,
                        2420
                      ],
                      "referencedDeclaration": 2420,
                      "src": "4520:3:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_internal_pure$_t_uint256_$_t_uint256_$_t_string_memory_ptr_$returns$_t_uint256_$",
                        "typeString": "function (uint256,uint256,string memory) pure returns (uint256)"
                      }
                    },
                    "id": 2393,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "4520:37:17",
                    "tryCall": false,
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 2388,
                  "id": 2394,
                  "nodeType": "Return",
                  "src": "4513:44:17"
                }
              ]
            },
            "documentation": {
              "id": 2380,
              "nodeType": "StructuredDocumentation",
              "src": "3991:440:17",
              "text": " @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n Reverts when dividing by zero.\n Counterpart to Solidity's `%` operator. This function uses a `revert`\n opcode (which leaves remaining gas untouched) while Solidity uses an\n invalid opcode to revert (consuming all remaining gas).\n Requirements:\n - The divisor cannot be zero."
            },
            "id": 2396,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "mod",
            "nodeType": "FunctionDefinition",
            "overrides": null,
            "parameters": {
              "id": 2385,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2382,
                  "mutability": "mutable",
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2396,
                  "src": "4449:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2381,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "4449:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 2384,
                  "mutability": "mutable",
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2396,
                  "src": "4460:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2383,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "4460:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "4448:22:17"
            },
            "returnParameters": {
              "id": 2388,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2387,
                  "mutability": "mutable",
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2396,
                  "src": "4494:7:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2386,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "4494:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "4493:9:17"
            },
            "scope": 2421,
            "src": "4436:128:17",
            "stateMutability": "pure",
            "virtual": false,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 2419,
              "nodeType": "Block",
              "src": "5130:68:17",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 2411,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 2409,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 2401,
                          "src": "5148:1:17",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": "!=",
                        "rightExpression": {
                          "argumentTypes": null,
                          "hexValue": "30",
                          "id": 2410,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": true,
                          "kind": "number",
                          "lValueRequested": false,
                          "nodeType": "Literal",
                          "src": "5153:1:17",
                          "subdenomination": null,
                          "typeDescriptions": {
                            "typeIdentifier": "t_rational_0_by_1",
                            "typeString": "int_const 0"
                          },
                          "value": "0"
                        },
                        "src": "5148:6:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "id": 2412,
                        "name": "errorMessage",
                        "nodeType": "Identifier",
                        "overloadedDeclarations": [],
                        "referencedDeclaration": 2403,
                        "src": "5156:12:17",
                        "typeDescriptions": {
                          "typeIdentifier": "t_string_memory_ptr",
                          "typeString": "string memory"
                        }
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        },
                        {
                          "typeIdentifier": "t_string_memory_ptr",
                          "typeString": "string memory"
                        }
                      ],
                      "id": 2408,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        -18,
                        -18
                      ],
                      "referencedDeclaration": -18,
                      "src": "5140:7:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 2413,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "5140:29:17",
                    "tryCall": false,
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 2414,
                  "nodeType": "ExpressionStatement",
                  "src": "5140:29:17"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 2417,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 2415,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 2399,
                      "src": "5186:1:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "%",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 2416,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 2401,
                      "src": "5190:1:17",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "5186:5:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 2407,
                  "id": 2418,
                  "nodeType": "Return",
                  "src": "5179:12:17"
                }
              ]
            },
            "documentation": {
              "id": 2397,
              "nodeType": "StructuredDocumentation",
              "src": "4570:460:17",
              "text": " @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\n Reverts with custom message when dividing by zero.\n Counterpart to Solidity's `%` operator. This function uses a `revert`\n opcode (which leaves remaining gas untouched) while Solidity uses an\n invalid opcode to revert (consuming all remaining gas).\n Requirements:\n - The divisor cannot be zero."
            },
            "id": 2420,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "mod",
            "nodeType": "FunctionDefinition",
            "overrides": null,
            "parameters": {
              "id": 2404,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2399,
                  "mutability": "mutable",
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2420,
                  "src": "5048:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2398,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "5048:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 2401,
                  "mutability": "mutable",
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2420,
                  "src": "5059:9:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2400,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "5059:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 2403,
                  "mutability": "mutable",
                  "name": "errorMessage",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2420,
                  "src": "5070:26:17",
                  "stateVariable": false,
                  "storageLocation": "memory",
                  "typeDescriptions": {
                    "typeIdentifier": "t_string_memory_ptr",
                    "typeString": "string"
                  },
                  "typeName": {
                    "id": 2402,
                    "name": "string",
                    "nodeType": "ElementaryTypeName",
                    "src": "5070:6:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_string_storage_ptr",
                      "typeString": "string"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "5047:50:17"
            },
            "returnParameters": {
              "id": 2407,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 2406,
                  "mutability": "mutable",
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "overrides": null,
                  "scope": 2420,
                  "src": "5121:7:17",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 2405,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "5121:7:17",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "5120:9:17"
            },
            "scope": 2421,
            "src": "5035:163:17",
            "stateMutability": "pure",
            "virtual": false,
            "visibility": "internal"
          }
        ],
        "scope": 2422,
        "src": "622:4578:17"
      }
    ],
    "src": "33:5168:17"
  },
  "bytecode": "0x60566023600b82828239805160001a607314601657fe5b30600052607381538281f3fe73000000000000000000000000000000000000000030146080604052600080fdfea26469706673582212206c41d69d92a75fb19d1a3219b08ca6025f4b99a3603e3a6bb297c4822902181264736f6c63430007000033",
  "deployedBytecode": "0x73000000000000000000000000000000000000000030146080604052600080fdfea26469706673582212206c41d69d92a75fb19d1a3219b08ca6025f4b99a3603e3a6bb297c4822902181264736f6c63430007000033",
  "compiler": {
    "name": "solc",
    "version": "0.7.0+commit.9e61f92b.Emscripten.clang",
    "optimizer": {
      "enabled": false,
      "runs": 200
    },
    "evmVersion": "petersburg"
  }
}
