Two's Complement

Two's complement is the way most computers represent negative integers.


There are three steps:

work out -19 in binary

1) Work out the number as a positive. 

00010011 <-- This equals 19. 

2) Inverse the number.

11101100

3) Add 1.

11101101 <-- This equals -19. 

Note: The first byte equalling 0 means the number is positive, the first byte equalling 1 means the number is negative.

The range of numbers that can be represented with Two's compliment is -128-127.



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