{
  "contractName": "SafeMath",
  "abi": [],
  "metadata": "{\"compiler\":{\"version\":\"0.5.6+commit.b259423e\"},\"language\":\"Solidity\",\"output\":{\"abi\":[],\"devdoc\":{\"details\":\"Wrappers over Solidity's arithmetic operations with added overflow checks. * Arithmetic operations in Solidity wrap on overflow. This can easily result in bugs, because programmers usually assume that an overflow raises an error, which is the standard behavior in high level programming languages. `SafeMath` restores this intuition by reverting the transaction when an operation overflows. * Using this library instead of the unchecked operations eliminates an entire class of bugs, so it's recommended to use it always.\",\"methods\":{}},\"userdoc\":{\"methods\":{}}},\"settings\":{\"compilationTarget\":{\"openzeppelin-solidity/contracts/math/SafeMath.sol\":\"SafeMath\"},\"evmVersion\":\"petersburg\",\"libraries\":{},\"optimizer\":{\"enabled\":false,\"runs\":200},\"remappings\":[]},\"sources\":{\"openzeppelin-solidity/contracts/math/SafeMath.sol\":{\"keccak256\":\"0x4ccf2d7b51873db1ccfd54ca2adae5eac3b184f9699911ed4490438419f1c690\",\"urls\":[\"bzzr://1604f5b6d6e916c154efd8c6720cda069e5ba32dfa0a9dedf2b42e5b02d07f89\"]}},\"version\":1}",
  "bytecode": "0x604c6023600b82828239805160001a607314601657fe5b30600052607381538281f3fe73000000000000000000000000000000000000000030146080604052600080fdfea165627a7a72305820130212d61880db48e559eed4a8080c245597fcd55de72bf4421c3e9c3f810e170029",
  "deployedBytecode": "0x73000000000000000000000000000000000000000030146080604052600080fdfea165627a7a72305820130212d61880db48e559eed4a8080c245597fcd55de72bf4421c3e9c3f810e170029",
  "sourceMap": "589:2938:32:-;;132:2:-1;166:7;155:9;146:7;137:37;255:7;249:14;246:1;241:23;235:4;232:33;222:2;;269:9;222:2;293:9;290:1;283:20;323:4;314:7;306:22;347:7;338;331:24",
  "deployedSourceMap": "589:2938:32:-;;;;;;;;",
  "source": "pragma solidity ^0.5.0;\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     * - 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     * - Subtraction cannot overflow.\n     */\n    function sub(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b <= a, \"SafeMath: subtraction overflow\");\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     * - 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-solidity/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     * - The divisor cannot be zero.\n     */\n    function div(uint256 a, uint256 b) internal pure returns (uint256) {\n        // Solidity only automatically asserts when dividing by 0\n        require(b > 0, \"SafeMath: division by zero\");\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     * - The divisor cannot be zero.\n     */\n    function mod(uint256 a, uint256 b) internal pure returns (uint256) {\n        require(b != 0, \"SafeMath: modulo by zero\");\n        return a % b;\n    }\n}\n",
  "sourcePath": "openzeppelin-solidity/contracts/math/SafeMath.sol",
  "ast": {
    "absolutePath": "openzeppelin-solidity/contracts/math/SafeMath.sol",
    "exportedSymbols": {
      "SafeMath": [
        7381
      ]
    },
    "id": 7382,
    "nodeType": "SourceUnit",
    "nodes": [
      {
        "id": 7250,
        "literals": [
          "solidity",
          "^",
          "0.5",
          ".0"
        ],
        "nodeType": "PragmaDirective",
        "src": "0:23:32"
      },
      {
        "baseContracts": [],
        "contractDependencies": [],
        "contractKind": "library",
        "documentation": "@dev Wrappers over Solidity's arithmetic operations with added overflow\nchecks.\n * Arithmetic operations in Solidity wrap on overflow. This can easily result\nin bugs, because programmers usually assume that an overflow raises an\nerror, which is the standard behavior in high level programming languages.\n`SafeMath` restores this intuition by reverting the transaction when an\noperation overflows.\n * Using this library instead of the unchecked operations eliminates an entire\nclass of bugs, so it's recommended to use it always.",
        "fullyImplemented": true,
        "id": 7381,
        "linearizedBaseContracts": [
          7381
        ],
        "name": "SafeMath",
        "nodeType": "ContractDefinition",
        "nodes": [
          {
            "body": {
              "id": 7274,
              "nodeType": "Block",
              "src": "901:109:32",
              "statements": [
                {
                  "assignments": [
                    7260
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 7260,
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "scope": 7274,
                      "src": "911:9:32",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 7259,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "911:7:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 7264,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7263,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7261,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7252,
                      "src": "923:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "+",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 7262,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7254,
                      "src": "927:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "923:5:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "911:17:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 7268,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 7266,
                          "name": "c",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7260,
                          "src": "946:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": ">=",
                        "rightExpression": {
                          "argumentTypes": null,
                          "id": 7267,
                          "name": "a",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7252,
                          "src": "951:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "src": "946:6:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206164646974696f6e206f766572666c6f77",
                        "id": 7269,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "954:29:32",
                        "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": 7265,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        7923,
                        7924
                      ],
                      "referencedDeclaration": 7924,
                      "src": "938:7:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 7270,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "938:46:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 7271,
                  "nodeType": "ExpressionStatement",
                  "src": "938:46:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 7272,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 7260,
                    "src": "1002:1:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 7258,
                  "id": 7273,
                  "nodeType": "Return",
                  "src": "995:8:32"
                }
              ]
            },
            "documentation": "@dev Returns the addition of two unsigned integers, reverting on\noverflow.\n     * Counterpart to Solidity's `+` operator.\n     * Requirements:\n- Addition cannot overflow.",
            "id": 7275,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "add",
            "nodeType": "FunctionDefinition",
            "parameters": {
              "id": 7255,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7252,
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "scope": 7275,
                  "src": "847:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7251,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "847:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 7254,
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "scope": 7275,
                  "src": "858:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7253,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "858:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "846:22:32"
            },
            "returnParameters": {
              "id": 7258,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7257,
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "scope": 7275,
                  "src": "892:7:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7256,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "892:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "891:9:32"
            },
            "scope": 7381,
            "src": "834:176:32",
            "stateMutability": "pure",
            "superFunction": null,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 7299,
              "nodeType": "Block",
              "src": "1341:112:32",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 7287,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 7285,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7279,
                          "src": "1359:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": "<=",
                        "rightExpression": {
                          "argumentTypes": null,
                          "id": 7286,
                          "name": "a",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7277,
                          "src": "1364:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "src": "1359:6:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a207375627472616374696f6e206f766572666c6f77",
                        "id": 7288,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "1367:32:32",
                        "subdenomination": null,
                        "typeDescriptions": {
                          "typeIdentifier": "t_stringliteral_50b058e9b5320e58880d88223c9801cd9eecdcf90323d5c2318bc1b6b916e862",
                          "typeString": "literal_string \"SafeMath: subtraction overflow\""
                        },
                        "value": "SafeMath: subtraction overflow"
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        },
                        {
                          "typeIdentifier": "t_stringliteral_50b058e9b5320e58880d88223c9801cd9eecdcf90323d5c2318bc1b6b916e862",
                          "typeString": "literal_string \"SafeMath: subtraction overflow\""
                        }
                      ],
                      "id": 7284,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        7923,
                        7924
                      ],
                      "referencedDeclaration": 7924,
                      "src": "1351:7:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 7289,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "1351:49:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 7290,
                  "nodeType": "ExpressionStatement",
                  "src": "1351:49:32"
                },
                {
                  "assignments": [
                    7292
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 7292,
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "scope": 7299,
                      "src": "1410:9:32",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 7291,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "1410:7:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 7296,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7295,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7293,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7277,
                      "src": "1422:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "-",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 7294,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7279,
                      "src": "1426:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "1422:5:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "1410:17:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 7297,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 7292,
                    "src": "1445:1:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 7283,
                  "id": 7298,
                  "nodeType": "Return",
                  "src": "1438:8:32"
                }
              ]
            },
            "documentation": "@dev Returns the subtraction of two unsigned integers, reverting on\noverflow (when the result is negative).\n     * Counterpart to Solidity's `-` operator.\n     * Requirements:\n- Subtraction cannot overflow.",
            "id": 7300,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "sub",
            "nodeType": "FunctionDefinition",
            "parameters": {
              "id": 7280,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7277,
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "scope": 7300,
                  "src": "1287:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7276,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1287:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 7279,
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "scope": 7300,
                  "src": "1298:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7278,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1298:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1286:22:32"
            },
            "returnParameters": {
              "id": 7283,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7282,
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "scope": 7300,
                  "src": "1332:7:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7281,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1332:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1331:9:32"
            },
            "scope": 7381,
            "src": "1274:179:32",
            "stateMutability": "pure",
            "superFunction": null,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 7333,
              "nodeType": "Block",
              "src": "1760:391:32",
              "statements": [
                {
                  "condition": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7311,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7309,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7302,
                      "src": "1991:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "==",
                    "rightExpression": {
                      "argumentTypes": null,
                      "hexValue": "30",
                      "id": 7310,
                      "isConstant": false,
                      "isLValue": false,
                      "isPure": true,
                      "kind": "number",
                      "lValueRequested": false,
                      "nodeType": "Literal",
                      "src": "1996:1:32",
                      "subdenomination": null,
                      "typeDescriptions": {
                        "typeIdentifier": "t_rational_0_by_1",
                        "typeString": "int_const 0"
                      },
                      "value": "0"
                    },
                    "src": "1991:6:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_bool",
                      "typeString": "bool"
                    }
                  },
                  "falseBody": null,
                  "id": 7315,
                  "nodeType": "IfStatement",
                  "src": "1987:45:32",
                  "trueBody": {
                    "id": 7314,
                    "nodeType": "Block",
                    "src": "1999:33:32",
                    "statements": [
                      {
                        "expression": {
                          "argumentTypes": null,
                          "hexValue": "30",
                          "id": 7312,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": true,
                          "kind": "number",
                          "lValueRequested": false,
                          "nodeType": "Literal",
                          "src": "2020:1:32",
                          "subdenomination": null,
                          "typeDescriptions": {
                            "typeIdentifier": "t_rational_0_by_1",
                            "typeString": "int_const 0"
                          },
                          "value": "0"
                        },
                        "functionReturnParameters": 7308,
                        "id": 7313,
                        "nodeType": "Return",
                        "src": "2013:8:32"
                      }
                    ]
                  }
                },
                {
                  "assignments": [
                    7317
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 7317,
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "scope": 7333,
                      "src": "2042:9:32",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 7316,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "2042:7:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 7321,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7320,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7318,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7302,
                      "src": "2054:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "*",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 7319,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7304,
                      "src": "2058:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "2054:5:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "2042:17:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 7327,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "commonType": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          },
                          "id": 7325,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": false,
                          "lValueRequested": false,
                          "leftExpression": {
                            "argumentTypes": null,
                            "id": 7323,
                            "name": "c",
                            "nodeType": "Identifier",
                            "overloadedDeclarations": [],
                            "referencedDeclaration": 7317,
                            "src": "2077:1:32",
                            "typeDescriptions": {
                              "typeIdentifier": "t_uint256",
                              "typeString": "uint256"
                            }
                          },
                          "nodeType": "BinaryOperation",
                          "operator": "/",
                          "rightExpression": {
                            "argumentTypes": null,
                            "id": 7324,
                            "name": "a",
                            "nodeType": "Identifier",
                            "overloadedDeclarations": [],
                            "referencedDeclaration": 7302,
                            "src": "2081:1:32",
                            "typeDescriptions": {
                              "typeIdentifier": "t_uint256",
                              "typeString": "uint256"
                            }
                          },
                          "src": "2077:5:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": "==",
                        "rightExpression": {
                          "argumentTypes": null,
                          "id": 7326,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7304,
                          "src": "2086:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "src": "2077:10:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206d756c7469706c69636174696f6e206f766572666c6f77",
                        "id": 7328,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "2089:35:32",
                        "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": 7322,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        7923,
                        7924
                      ],
                      "referencedDeclaration": 7924,
                      "src": "2069:7:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 7329,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "2069:56:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 7330,
                  "nodeType": "ExpressionStatement",
                  "src": "2069:56:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 7331,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 7317,
                    "src": "2143:1:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 7308,
                  "id": 7332,
                  "nodeType": "Return",
                  "src": "2136:8:32"
                }
              ]
            },
            "documentation": "@dev Returns the multiplication of two unsigned integers, reverting on\noverflow.\n     * Counterpart to Solidity's `*` operator.\n     * Requirements:\n- Multiplication cannot overflow.",
            "id": 7334,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "mul",
            "nodeType": "FunctionDefinition",
            "parameters": {
              "id": 7305,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7302,
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "scope": 7334,
                  "src": "1706:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7301,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1706:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 7304,
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "scope": 7334,
                  "src": "1717:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7303,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1717:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1705:22:32"
            },
            "returnParameters": {
              "id": 7308,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7307,
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "scope": 7334,
                  "src": "1751:7:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7306,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1751:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1750:9:32"
            },
            "scope": 7381,
            "src": "1693:458:32",
            "stateMutability": "pure",
            "superFunction": null,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 7358,
              "nodeType": "Block",
              "src": "2673:259:32",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 7346,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 7344,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7338,
                          "src": "2757:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": ">",
                        "rightExpression": {
                          "argumentTypes": null,
                          "hexValue": "30",
                          "id": 7345,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": true,
                          "kind": "number",
                          "lValueRequested": false,
                          "nodeType": "Literal",
                          "src": "2761:1:32",
                          "subdenomination": null,
                          "typeDescriptions": {
                            "typeIdentifier": "t_rational_0_by_1",
                            "typeString": "int_const 0"
                          },
                          "value": "0"
                        },
                        "src": "2757:5:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206469766973696f6e206279207a65726f",
                        "id": 7347,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "2764:28:32",
                        "subdenomination": null,
                        "typeDescriptions": {
                          "typeIdentifier": "t_stringliteral_5b7cc70dda4dc2143e5adb63bd5d1f349504f461dbdfd9bc76fac1f8ca6d019f",
                          "typeString": "literal_string \"SafeMath: division by zero\""
                        },
                        "value": "SafeMath: division by zero"
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        },
                        {
                          "typeIdentifier": "t_stringliteral_5b7cc70dda4dc2143e5adb63bd5d1f349504f461dbdfd9bc76fac1f8ca6d019f",
                          "typeString": "literal_string \"SafeMath: division by zero\""
                        }
                      ],
                      "id": 7343,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        7923,
                        7924
                      ],
                      "referencedDeclaration": 7924,
                      "src": "2749:7:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 7348,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "2749:44:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 7349,
                  "nodeType": "ExpressionStatement",
                  "src": "2749:44:32"
                },
                {
                  "assignments": [
                    7351
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 7351,
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "scope": 7358,
                      "src": "2803:9:32",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 7350,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "2803:7:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 7355,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7354,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7352,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7336,
                      "src": "2815:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "/",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 7353,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7338,
                      "src": "2819:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "2815:5:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "2803:17:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 7356,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 7351,
                    "src": "2924:1:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 7342,
                  "id": 7357,
                  "nodeType": "Return",
                  "src": "2917:8:32"
                }
              ]
            },
            "documentation": "@dev Returns the integer division of two unsigned integers. Reverts on\ndivision 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\nuses an invalid opcode to revert (consuming all remaining gas).\n     * Requirements:\n- The divisor cannot be zero.",
            "id": 7359,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "div",
            "nodeType": "FunctionDefinition",
            "parameters": {
              "id": 7339,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7336,
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "scope": 7359,
                  "src": "2619:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7335,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "2619:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 7338,
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "scope": 7359,
                  "src": "2630:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7337,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "2630:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "2618:22:32"
            },
            "returnParameters": {
              "id": 7342,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7341,
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "scope": 7359,
                  "src": "2664:7:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7340,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "2664:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "2663:9:32"
            },
            "scope": 7381,
            "src": "2606:326:32",
            "stateMutability": "pure",
            "superFunction": null,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 7379,
              "nodeType": "Block",
              "src": "3443:82:32",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 7371,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 7369,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7363,
                          "src": "3461:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": "!=",
                        "rightExpression": {
                          "argumentTypes": null,
                          "hexValue": "30",
                          "id": 7370,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": true,
                          "kind": "number",
                          "lValueRequested": false,
                          "nodeType": "Literal",
                          "src": "3466:1:32",
                          "subdenomination": null,
                          "typeDescriptions": {
                            "typeIdentifier": "t_rational_0_by_1",
                            "typeString": "int_const 0"
                          },
                          "value": "0"
                        },
                        "src": "3461:6:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206d6f64756c6f206279207a65726f",
                        "id": 7372,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "3469:26:32",
                        "subdenomination": null,
                        "typeDescriptions": {
                          "typeIdentifier": "t_stringliteral_726e51f7b81fce0a68f5f214f445e275313b20b1633f08ce954ee39abf8d7832",
                          "typeString": "literal_string \"SafeMath: modulo by zero\""
                        },
                        "value": "SafeMath: modulo by zero"
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        },
                        {
                          "typeIdentifier": "t_stringliteral_726e51f7b81fce0a68f5f214f445e275313b20b1633f08ce954ee39abf8d7832",
                          "typeString": "literal_string \"SafeMath: modulo by zero\""
                        }
                      ],
                      "id": 7368,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        7923,
                        7924
                      ],
                      "referencedDeclaration": 7924,
                      "src": "3453:7:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 7373,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "3453:43:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 7374,
                  "nodeType": "ExpressionStatement",
                  "src": "3453:43:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7377,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7375,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7361,
                      "src": "3513:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "%",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 7376,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7363,
                      "src": "3517:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "3513:5:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 7367,
                  "id": 7378,
                  "nodeType": "Return",
                  "src": "3506:12:32"
                }
              ]
            },
            "documentation": "@dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\nReverts when dividing by zero.\n     * Counterpart to Solidity's `%` operator. This function uses a `revert`\nopcode (which leaves remaining gas untouched) while Solidity uses an\ninvalid opcode to revert (consuming all remaining gas).\n     * Requirements:\n- The divisor cannot be zero.",
            "id": 7380,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "mod",
            "nodeType": "FunctionDefinition",
            "parameters": {
              "id": 7364,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7361,
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "scope": 7380,
                  "src": "3389:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7360,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3389:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 7363,
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "scope": 7380,
                  "src": "3400:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7362,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3400:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "3388:22:32"
            },
            "returnParameters": {
              "id": 7367,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7366,
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "scope": 7380,
                  "src": "3434:7:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7365,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3434:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "3433:9:32"
            },
            "scope": 7381,
            "src": "3376:149:32",
            "stateMutability": "pure",
            "superFunction": null,
            "visibility": "internal"
          }
        ],
        "scope": 7382,
        "src": "589:2938:32"
      }
    ],
    "src": "0:3528:32"
  },
  "legacyAST": {
    "absolutePath": "openzeppelin-solidity/contracts/math/SafeMath.sol",
    "exportedSymbols": {
      "SafeMath": [
        7381
      ]
    },
    "id": 7382,
    "nodeType": "SourceUnit",
    "nodes": [
      {
        "id": 7250,
        "literals": [
          "solidity",
          "^",
          "0.5",
          ".0"
        ],
        "nodeType": "PragmaDirective",
        "src": "0:23:32"
      },
      {
        "baseContracts": [],
        "contractDependencies": [],
        "contractKind": "library",
        "documentation": "@dev Wrappers over Solidity's arithmetic operations with added overflow\nchecks.\n * Arithmetic operations in Solidity wrap on overflow. This can easily result\nin bugs, because programmers usually assume that an overflow raises an\nerror, which is the standard behavior in high level programming languages.\n`SafeMath` restores this intuition by reverting the transaction when an\noperation overflows.\n * Using this library instead of the unchecked operations eliminates an entire\nclass of bugs, so it's recommended to use it always.",
        "fullyImplemented": true,
        "id": 7381,
        "linearizedBaseContracts": [
          7381
        ],
        "name": "SafeMath",
        "nodeType": "ContractDefinition",
        "nodes": [
          {
            "body": {
              "id": 7274,
              "nodeType": "Block",
              "src": "901:109:32",
              "statements": [
                {
                  "assignments": [
                    7260
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 7260,
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "scope": 7274,
                      "src": "911:9:32",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 7259,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "911:7:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 7264,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7263,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7261,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7252,
                      "src": "923:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "+",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 7262,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7254,
                      "src": "927:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "923:5:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "911:17:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 7268,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 7266,
                          "name": "c",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7260,
                          "src": "946:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": ">=",
                        "rightExpression": {
                          "argumentTypes": null,
                          "id": 7267,
                          "name": "a",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7252,
                          "src": "951:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "src": "946:6:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206164646974696f6e206f766572666c6f77",
                        "id": 7269,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "954:29:32",
                        "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": 7265,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        7923,
                        7924
                      ],
                      "referencedDeclaration": 7924,
                      "src": "938:7:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 7270,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "938:46:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 7271,
                  "nodeType": "ExpressionStatement",
                  "src": "938:46:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 7272,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 7260,
                    "src": "1002:1:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 7258,
                  "id": 7273,
                  "nodeType": "Return",
                  "src": "995:8:32"
                }
              ]
            },
            "documentation": "@dev Returns the addition of two unsigned integers, reverting on\noverflow.\n     * Counterpart to Solidity's `+` operator.\n     * Requirements:\n- Addition cannot overflow.",
            "id": 7275,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "add",
            "nodeType": "FunctionDefinition",
            "parameters": {
              "id": 7255,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7252,
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "scope": 7275,
                  "src": "847:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7251,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "847:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 7254,
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "scope": 7275,
                  "src": "858:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7253,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "858:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "846:22:32"
            },
            "returnParameters": {
              "id": 7258,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7257,
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "scope": 7275,
                  "src": "892:7:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7256,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "892:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "891:9:32"
            },
            "scope": 7381,
            "src": "834:176:32",
            "stateMutability": "pure",
            "superFunction": null,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 7299,
              "nodeType": "Block",
              "src": "1341:112:32",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 7287,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 7285,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7279,
                          "src": "1359:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": "<=",
                        "rightExpression": {
                          "argumentTypes": null,
                          "id": 7286,
                          "name": "a",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7277,
                          "src": "1364:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "src": "1359:6:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a207375627472616374696f6e206f766572666c6f77",
                        "id": 7288,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "1367:32:32",
                        "subdenomination": null,
                        "typeDescriptions": {
                          "typeIdentifier": "t_stringliteral_50b058e9b5320e58880d88223c9801cd9eecdcf90323d5c2318bc1b6b916e862",
                          "typeString": "literal_string \"SafeMath: subtraction overflow\""
                        },
                        "value": "SafeMath: subtraction overflow"
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        },
                        {
                          "typeIdentifier": "t_stringliteral_50b058e9b5320e58880d88223c9801cd9eecdcf90323d5c2318bc1b6b916e862",
                          "typeString": "literal_string \"SafeMath: subtraction overflow\""
                        }
                      ],
                      "id": 7284,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        7923,
                        7924
                      ],
                      "referencedDeclaration": 7924,
                      "src": "1351:7:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 7289,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "1351:49:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 7290,
                  "nodeType": "ExpressionStatement",
                  "src": "1351:49:32"
                },
                {
                  "assignments": [
                    7292
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 7292,
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "scope": 7299,
                      "src": "1410:9:32",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 7291,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "1410:7:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 7296,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7295,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7293,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7277,
                      "src": "1422:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "-",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 7294,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7279,
                      "src": "1426:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "1422:5:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "1410:17:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 7297,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 7292,
                    "src": "1445:1:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 7283,
                  "id": 7298,
                  "nodeType": "Return",
                  "src": "1438:8:32"
                }
              ]
            },
            "documentation": "@dev Returns the subtraction of two unsigned integers, reverting on\noverflow (when the result is negative).\n     * Counterpart to Solidity's `-` operator.\n     * Requirements:\n- Subtraction cannot overflow.",
            "id": 7300,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "sub",
            "nodeType": "FunctionDefinition",
            "parameters": {
              "id": 7280,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7277,
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "scope": 7300,
                  "src": "1287:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7276,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1287:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 7279,
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "scope": 7300,
                  "src": "1298:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7278,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1298:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1286:22:32"
            },
            "returnParameters": {
              "id": 7283,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7282,
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "scope": 7300,
                  "src": "1332:7:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7281,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1332:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1331:9:32"
            },
            "scope": 7381,
            "src": "1274:179:32",
            "stateMutability": "pure",
            "superFunction": null,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 7333,
              "nodeType": "Block",
              "src": "1760:391:32",
              "statements": [
                {
                  "condition": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7311,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7309,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7302,
                      "src": "1991:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "==",
                    "rightExpression": {
                      "argumentTypes": null,
                      "hexValue": "30",
                      "id": 7310,
                      "isConstant": false,
                      "isLValue": false,
                      "isPure": true,
                      "kind": "number",
                      "lValueRequested": false,
                      "nodeType": "Literal",
                      "src": "1996:1:32",
                      "subdenomination": null,
                      "typeDescriptions": {
                        "typeIdentifier": "t_rational_0_by_1",
                        "typeString": "int_const 0"
                      },
                      "value": "0"
                    },
                    "src": "1991:6:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_bool",
                      "typeString": "bool"
                    }
                  },
                  "falseBody": null,
                  "id": 7315,
                  "nodeType": "IfStatement",
                  "src": "1987:45:32",
                  "trueBody": {
                    "id": 7314,
                    "nodeType": "Block",
                    "src": "1999:33:32",
                    "statements": [
                      {
                        "expression": {
                          "argumentTypes": null,
                          "hexValue": "30",
                          "id": 7312,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": true,
                          "kind": "number",
                          "lValueRequested": false,
                          "nodeType": "Literal",
                          "src": "2020:1:32",
                          "subdenomination": null,
                          "typeDescriptions": {
                            "typeIdentifier": "t_rational_0_by_1",
                            "typeString": "int_const 0"
                          },
                          "value": "0"
                        },
                        "functionReturnParameters": 7308,
                        "id": 7313,
                        "nodeType": "Return",
                        "src": "2013:8:32"
                      }
                    ]
                  }
                },
                {
                  "assignments": [
                    7317
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 7317,
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "scope": 7333,
                      "src": "2042:9:32",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 7316,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "2042:7:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 7321,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7320,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7318,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7302,
                      "src": "2054:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "*",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 7319,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7304,
                      "src": "2058:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "2054:5:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "2042:17:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 7327,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "commonType": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          },
                          "id": 7325,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": false,
                          "lValueRequested": false,
                          "leftExpression": {
                            "argumentTypes": null,
                            "id": 7323,
                            "name": "c",
                            "nodeType": "Identifier",
                            "overloadedDeclarations": [],
                            "referencedDeclaration": 7317,
                            "src": "2077:1:32",
                            "typeDescriptions": {
                              "typeIdentifier": "t_uint256",
                              "typeString": "uint256"
                            }
                          },
                          "nodeType": "BinaryOperation",
                          "operator": "/",
                          "rightExpression": {
                            "argumentTypes": null,
                            "id": 7324,
                            "name": "a",
                            "nodeType": "Identifier",
                            "overloadedDeclarations": [],
                            "referencedDeclaration": 7302,
                            "src": "2081:1:32",
                            "typeDescriptions": {
                              "typeIdentifier": "t_uint256",
                              "typeString": "uint256"
                            }
                          },
                          "src": "2077:5:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": "==",
                        "rightExpression": {
                          "argumentTypes": null,
                          "id": 7326,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7304,
                          "src": "2086:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "src": "2077:10:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206d756c7469706c69636174696f6e206f766572666c6f77",
                        "id": 7328,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "2089:35:32",
                        "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": 7322,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        7923,
                        7924
                      ],
                      "referencedDeclaration": 7924,
                      "src": "2069:7:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 7329,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "2069:56:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 7330,
                  "nodeType": "ExpressionStatement",
                  "src": "2069:56:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 7331,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 7317,
                    "src": "2143:1:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 7308,
                  "id": 7332,
                  "nodeType": "Return",
                  "src": "2136:8:32"
                }
              ]
            },
            "documentation": "@dev Returns the multiplication of two unsigned integers, reverting on\noverflow.\n     * Counterpart to Solidity's `*` operator.\n     * Requirements:\n- Multiplication cannot overflow.",
            "id": 7334,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "mul",
            "nodeType": "FunctionDefinition",
            "parameters": {
              "id": 7305,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7302,
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "scope": 7334,
                  "src": "1706:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7301,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1706:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 7304,
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "scope": 7334,
                  "src": "1717:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7303,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1717:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1705:22:32"
            },
            "returnParameters": {
              "id": 7308,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7307,
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "scope": 7334,
                  "src": "1751:7:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7306,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "1751:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "1750:9:32"
            },
            "scope": 7381,
            "src": "1693:458:32",
            "stateMutability": "pure",
            "superFunction": null,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 7358,
              "nodeType": "Block",
              "src": "2673:259:32",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 7346,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 7344,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7338,
                          "src": "2757:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": ">",
                        "rightExpression": {
                          "argumentTypes": null,
                          "hexValue": "30",
                          "id": 7345,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": true,
                          "kind": "number",
                          "lValueRequested": false,
                          "nodeType": "Literal",
                          "src": "2761:1:32",
                          "subdenomination": null,
                          "typeDescriptions": {
                            "typeIdentifier": "t_rational_0_by_1",
                            "typeString": "int_const 0"
                          },
                          "value": "0"
                        },
                        "src": "2757:5:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206469766973696f6e206279207a65726f",
                        "id": 7347,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "2764:28:32",
                        "subdenomination": null,
                        "typeDescriptions": {
                          "typeIdentifier": "t_stringliteral_5b7cc70dda4dc2143e5adb63bd5d1f349504f461dbdfd9bc76fac1f8ca6d019f",
                          "typeString": "literal_string \"SafeMath: division by zero\""
                        },
                        "value": "SafeMath: division by zero"
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        },
                        {
                          "typeIdentifier": "t_stringliteral_5b7cc70dda4dc2143e5adb63bd5d1f349504f461dbdfd9bc76fac1f8ca6d019f",
                          "typeString": "literal_string \"SafeMath: division by zero\""
                        }
                      ],
                      "id": 7343,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        7923,
                        7924
                      ],
                      "referencedDeclaration": 7924,
                      "src": "2749:7:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 7348,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "2749:44:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 7349,
                  "nodeType": "ExpressionStatement",
                  "src": "2749:44:32"
                },
                {
                  "assignments": [
                    7351
                  ],
                  "declarations": [
                    {
                      "constant": false,
                      "id": 7351,
                      "name": "c",
                      "nodeType": "VariableDeclaration",
                      "scope": 7358,
                      "src": "2803:9:32",
                      "stateVariable": false,
                      "storageLocation": "default",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      },
                      "typeName": {
                        "id": 7350,
                        "name": "uint256",
                        "nodeType": "ElementaryTypeName",
                        "src": "2803:7:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        }
                      },
                      "value": null,
                      "visibility": "internal"
                    }
                  ],
                  "id": 7355,
                  "initialValue": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7354,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7352,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7336,
                      "src": "2815:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "/",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 7353,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7338,
                      "src": "2819:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "2815:5:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "nodeType": "VariableDeclarationStatement",
                  "src": "2803:17:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "id": 7356,
                    "name": "c",
                    "nodeType": "Identifier",
                    "overloadedDeclarations": [],
                    "referencedDeclaration": 7351,
                    "src": "2924:1:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 7342,
                  "id": 7357,
                  "nodeType": "Return",
                  "src": "2917:8:32"
                }
              ]
            },
            "documentation": "@dev Returns the integer division of two unsigned integers. Reverts on\ndivision 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\nuses an invalid opcode to revert (consuming all remaining gas).\n     * Requirements:\n- The divisor cannot be zero.",
            "id": 7359,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "div",
            "nodeType": "FunctionDefinition",
            "parameters": {
              "id": 7339,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7336,
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "scope": 7359,
                  "src": "2619:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7335,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "2619:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 7338,
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "scope": 7359,
                  "src": "2630:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7337,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "2630:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "2618:22:32"
            },
            "returnParameters": {
              "id": 7342,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7341,
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "scope": 7359,
                  "src": "2664:7:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7340,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "2664:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "2663:9:32"
            },
            "scope": 7381,
            "src": "2606:326:32",
            "stateMutability": "pure",
            "superFunction": null,
            "visibility": "internal"
          },
          {
            "body": {
              "id": 7379,
              "nodeType": "Block",
              "src": "3443:82:32",
              "statements": [
                {
                  "expression": {
                    "argumentTypes": null,
                    "arguments": [
                      {
                        "argumentTypes": null,
                        "commonType": {
                          "typeIdentifier": "t_uint256",
                          "typeString": "uint256"
                        },
                        "id": 7371,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": false,
                        "lValueRequested": false,
                        "leftExpression": {
                          "argumentTypes": null,
                          "id": 7369,
                          "name": "b",
                          "nodeType": "Identifier",
                          "overloadedDeclarations": [],
                          "referencedDeclaration": 7363,
                          "src": "3461:1:32",
                          "typeDescriptions": {
                            "typeIdentifier": "t_uint256",
                            "typeString": "uint256"
                          }
                        },
                        "nodeType": "BinaryOperation",
                        "operator": "!=",
                        "rightExpression": {
                          "argumentTypes": null,
                          "hexValue": "30",
                          "id": 7370,
                          "isConstant": false,
                          "isLValue": false,
                          "isPure": true,
                          "kind": "number",
                          "lValueRequested": false,
                          "nodeType": "Literal",
                          "src": "3466:1:32",
                          "subdenomination": null,
                          "typeDescriptions": {
                            "typeIdentifier": "t_rational_0_by_1",
                            "typeString": "int_const 0"
                          },
                          "value": "0"
                        },
                        "src": "3461:6:32",
                        "typeDescriptions": {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        }
                      },
                      {
                        "argumentTypes": null,
                        "hexValue": "536166654d6174683a206d6f64756c6f206279207a65726f",
                        "id": 7372,
                        "isConstant": false,
                        "isLValue": false,
                        "isPure": true,
                        "kind": "string",
                        "lValueRequested": false,
                        "nodeType": "Literal",
                        "src": "3469:26:32",
                        "subdenomination": null,
                        "typeDescriptions": {
                          "typeIdentifier": "t_stringliteral_726e51f7b81fce0a68f5f214f445e275313b20b1633f08ce954ee39abf8d7832",
                          "typeString": "literal_string \"SafeMath: modulo by zero\""
                        },
                        "value": "SafeMath: modulo by zero"
                      }
                    ],
                    "expression": {
                      "argumentTypes": [
                        {
                          "typeIdentifier": "t_bool",
                          "typeString": "bool"
                        },
                        {
                          "typeIdentifier": "t_stringliteral_726e51f7b81fce0a68f5f214f445e275313b20b1633f08ce954ee39abf8d7832",
                          "typeString": "literal_string \"SafeMath: modulo by zero\""
                        }
                      ],
                      "id": 7368,
                      "name": "require",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [
                        7923,
                        7924
                      ],
                      "referencedDeclaration": 7924,
                      "src": "3453:7:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_function_require_pure$_t_bool_$_t_string_memory_ptr_$returns$__$",
                        "typeString": "function (bool,string memory) pure"
                      }
                    },
                    "id": 7373,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "kind": "functionCall",
                    "lValueRequested": false,
                    "names": [],
                    "nodeType": "FunctionCall",
                    "src": "3453:43:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_tuple$__$",
                      "typeString": "tuple()"
                    }
                  },
                  "id": 7374,
                  "nodeType": "ExpressionStatement",
                  "src": "3453:43:32"
                },
                {
                  "expression": {
                    "argumentTypes": null,
                    "commonType": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    },
                    "id": 7377,
                    "isConstant": false,
                    "isLValue": false,
                    "isPure": false,
                    "lValueRequested": false,
                    "leftExpression": {
                      "argumentTypes": null,
                      "id": 7375,
                      "name": "a",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7361,
                      "src": "3513:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "nodeType": "BinaryOperation",
                    "operator": "%",
                    "rightExpression": {
                      "argumentTypes": null,
                      "id": 7376,
                      "name": "b",
                      "nodeType": "Identifier",
                      "overloadedDeclarations": [],
                      "referencedDeclaration": 7363,
                      "src": "3517:1:32",
                      "typeDescriptions": {
                        "typeIdentifier": "t_uint256",
                        "typeString": "uint256"
                      }
                    },
                    "src": "3513:5:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "functionReturnParameters": 7367,
                  "id": 7378,
                  "nodeType": "Return",
                  "src": "3506:12:32"
                }
              ]
            },
            "documentation": "@dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),\nReverts when dividing by zero.\n     * Counterpart to Solidity's `%` operator. This function uses a `revert`\nopcode (which leaves remaining gas untouched) while Solidity uses an\ninvalid opcode to revert (consuming all remaining gas).\n     * Requirements:\n- The divisor cannot be zero.",
            "id": 7380,
            "implemented": true,
            "kind": "function",
            "modifiers": [],
            "name": "mod",
            "nodeType": "FunctionDefinition",
            "parameters": {
              "id": 7364,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7361,
                  "name": "a",
                  "nodeType": "VariableDeclaration",
                  "scope": 7380,
                  "src": "3389:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7360,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3389:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                },
                {
                  "constant": false,
                  "id": 7363,
                  "name": "b",
                  "nodeType": "VariableDeclaration",
                  "scope": 7380,
                  "src": "3400:9:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7362,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3400:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "3388:22:32"
            },
            "returnParameters": {
              "id": 7367,
              "nodeType": "ParameterList",
              "parameters": [
                {
                  "constant": false,
                  "id": 7366,
                  "name": "",
                  "nodeType": "VariableDeclaration",
                  "scope": 7380,
                  "src": "3434:7:32",
                  "stateVariable": false,
                  "storageLocation": "default",
                  "typeDescriptions": {
                    "typeIdentifier": "t_uint256",
                    "typeString": "uint256"
                  },
                  "typeName": {
                    "id": 7365,
                    "name": "uint256",
                    "nodeType": "ElementaryTypeName",
                    "src": "3434:7:32",
                    "typeDescriptions": {
                      "typeIdentifier": "t_uint256",
                      "typeString": "uint256"
                    }
                  },
                  "value": null,
                  "visibility": "internal"
                }
              ],
              "src": "3433:9:32"
            },
            "scope": 7381,
            "src": "3376:149:32",
            "stateMutability": "pure",
            "superFunction": null,
            "visibility": "internal"
          }
        ],
        "scope": 7382,
        "src": "589:2938:32"
      }
    ],
    "src": "0:3528:32"
  },
  "compiler": {
    "name": "solc",
    "version": "0.5.6+commit.b259423e.Emscripten.clang"
  },
  "networks": {},
  "schemaVersion": "3.0.11",
  "updatedAt": "2019-09-20T17:46:52.254Z",
  "devdoc": {
    "details": "Wrappers over Solidity's arithmetic operations with added overflow checks. * Arithmetic operations in Solidity wrap on overflow. This can easily result in bugs, because programmers usually assume that an overflow raises an error, which is the standard behavior in high level programming languages. `SafeMath` restores this intuition by reverting the transaction when an operation overflows. * Using this library instead of the unchecked operations eliminates an entire class of bugs, so it's recommended to use it always.",
    "methods": {}
  },
  "userdoc": {
    "methods": {}
  }
}