ONESCOMPLEMENT
Ones' complement
The ones' complement of a binary number is defined as the value obtained by inverting all the bits in the binary representation of the number . The ones' complement of the number then behaves like the negative of the original number in some arithmetic operations. To within a constant, the ones' complement behaves like the negative of the original number with binary addition. However, unlike two's complement, these numbers have not seen widespread use because of issues such as the offset of −1, that negating zero results in a distinct negative zero bit pattern, less simplicity with arithmetic borrowing, etc.The above text is a snippet from Wikipedia: Ones' complement
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