54 lines
1.1 KiB
Solidity
54 lines
1.1 KiB
Solidity
pragma solidity ^0.4.8;
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/**
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* Math operations with safety checks
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*/
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contract SafeMath {
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function safeMul(uint a, uint b) internal returns (uint) {
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uint c = a * b;
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assert(a == 0 || c / a == b);
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return c;
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}
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function safeDiv(uint a, uint b) internal returns (uint) {
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assert(b > 0);
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uint c = a / b;
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assert(a == b * c + a % b);
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return c;
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}
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function safeSub(uint a, uint b) internal returns (uint) {
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assert(b <= a);
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return a - b;
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}
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function safeAdd(uint a, uint b) internal returns (uint) {
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uint c = a + b;
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assert(c >= a);
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return c;
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}
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function max64(uint64 a, uint64 b) internal constant returns (uint64) {
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return a >= b ? a : b;
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}
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function min64(uint64 a, uint64 b) internal constant returns (uint64) {
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return a < b ? a : b;
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}
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function max256(uint256 a, uint256 b) internal constant returns (uint256) {
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return a >= b ? a : b;
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}
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function min256(uint256 a, uint256 b) internal constant returns (uint256) {
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return a < b ? a : b;
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}
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function assert(bool assertion) internal {
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if (!assertion) {
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throw;
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}
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}
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}
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