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FullMath

Facilitates multiplication and division that can have overflow of an intermediate value without any loss of precision

Handles "phantom overflow" i.e., allows multiplication and division where an intermediate value overflows 256 bits

Functions#

mulDiv#

function mulDiv(
uint256 a,
uint256 b,
uint256 denominator
) internal pure returns (uint256 result)

Calculates floor(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0

Credit to Remco Bloemen under MIT license https://xn--2-umb.com/21/muldiv

Parameters:#

NameTypeDescription
auint256The multiplicand
buint256The multiplier
denominatoruint256The divisor

Return Values:#

NameTypeDescription
resultuint256The 256-bit result

mulDivRoundingUp#

function mulDivRoundingUp(
uint256 a,
uint256 b,
uint256 denominator
) internal pure returns (uint256 result)

Calculates ceil(a×b÷denominator) with full precision. Throws if result overflows a uint256 or denominator == 0

Parameters:#

NameTypeDescription
auint256The multiplicand
buint256The multiplier
denominatoruint256The divisor

Return Values:#

NameTypeDescription
resultuint256The 256-bit result