# N bit Binary adder-subtractor discussion with `circuit`

and `example.`

Prerequisites Half-Adder, Full-Adder, Binary-Adder.

**Introduction:- **

Binary addition or subtraction can be implemented using a single circuit as discussed below. With this implementation any length (no of bits = N) of binary numbers can be used to calculate the results by using N number of full-adders and N number of XOR gates.

Circuit is very similar to binary adder circuit except of a XOR gate at second input to full-adders.

**Next, we will draw a circuit for adder-subtractor.**