# ones-complement

Noun

(*plural* ones' complements)

- (computing) The number obtained by subtracting a given
*n*-digit binary number from (which yields the same result as the logical complement).*The ones' complement of 0xAAAA is 0x5555 on a 16-bit machine, and 0xFFFF5555 on a 32-bit machine.*

- (computing) The convention by which bit patterns with high bit 0 represent positive numbers from 0 to directly, while bit patterns with high bit 1 represent negative numbers from 0 to ,
*n*being the word size of the machine, and the numeric complement of a number is its ones' complement.*Computers that use ones' complement arithmetic have two representations for zero, all 0's and all 1's.*