complement method of binary subtraction
This method is used for subtraction as subtraction is converted to addition.
Use following steps to perform subtraction ;
Write the first(positive ) number in original form.
Find the 2 s complement form of the second(negative ) number.
Add positive number with 2 complement form of the negative number.
If carry is generated then neglect the carry remaining answer will be the answer of the subtraction. The will be the case when positive number is more then the negative number.
If carry is not generated then the answer is negative and is in 2 complement form. This will be the case when negative number is more than the positive number.