(2) One's Complement Subtraction. The same basic steps for subtraction apply in one's
complement subtraction that are applied in two's complement subtraction, with very little change in the
procedure. To one's complement a number, just turn the ones into zeros and the zeros into ones.
To subtract the following:
NOTE: IF THE CARRY BIT IS 1, THEN END AROUND CARRY AND ADD. THE ANSWER IS
POSITIVE. IF THE CARRY BIT IS 0, THEN ONE'S COMPLEMENT THE ANSWER. THE
ANSWER IS NEGATIVE.
Using these two numbers and subtracting with the ones complement method, we find NO CARRY BIT.
We must then one's complement the answer, and place a negative sign before the number.
-1000: THE ANSWER