87 lines
1.5 KiB
Solidity
87 lines
1.5 KiB
Solidity
pragma solidity 0.4.24;
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contract SafeMath {
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function safeMul(uint256 a, uint256 b)
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internal
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pure
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returns (uint256)
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{
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if (a == 0) {
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return 0;
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}
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uint256 c = a * b;
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require(
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c / a == b,
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"UINT256_OVERFLOW"
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);
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return c;
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}
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function safeDiv(uint256 a, uint256 b)
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internal
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pure
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returns (uint256)
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{
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uint256 c = a / b;
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return c;
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}
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function safeSub(uint256 a, uint256 b)
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internal
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pure
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returns (uint256)
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{
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require(
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b <= a,
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"UINT256_UNDERFLOW"
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);
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return a - b;
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}
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function safeAdd(uint256 a, uint256 b)
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internal
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pure
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returns (uint256)
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{
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uint256 c = a + b;
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require(
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c >= a,
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"UINT256_OVERFLOW"
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);
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return c;
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}
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function max64(uint64 a, uint64 b)
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internal
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pure
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returns (uint256)
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{
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return a >= b ? a : b;
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}
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function min64(uint64 a, uint64 b)
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internal
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pure
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returns (uint256)
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{
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return a < b ? a : b;
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}
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function max256(uint256 a, uint256 b)
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internal
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pure
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returns (uint256)
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{
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return a >= b ? a : b;
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}
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function min256(uint256 a, uint256 b)
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internal
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pure
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returns (uint256)
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{
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return a < b ? a : b;
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}
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}
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