solidity/test/compilationTests/zeppelin/math/SafeMath.sol

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pragma solidity ^0.4.11;
/**
* @title SafeMath
* @dev Math operations with safety checks that throw on error
*/
library SafeMath {
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function mul(uint256 a, uint256 b) internal pure returns (uint256) {
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uint256 c = a * b;
assert(a == 0 || c / a == b);
return c;
}
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function div(uint256 a, uint256 b) internal pure returns (uint256) {
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// assert(b > 0); // Solidity automatically throws when dividing by 0
uint256 c = a / b;
// assert(a == b * c + a % b); // There is no case in which this doesn't hold
return c;
}
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function sub(uint256 a, uint256 b) internal pure returns (uint256) {
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assert(b <= a);
return a - b;
}
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function add(uint256 a, uint256 b) internal pure returns (uint256) {
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uint256 c = a + b;
assert(c >= a);
return c;
}
}