Draw the logic circuit for a haly adder using nand gates only?

____

____ c ----->|xor |------------> s

a ->|xor |-+------------>|____|

b ->|____| | _____ _____

+--->|nand |------>|nand |--> c

c ----->|_____| +-->|_____|

_____ |

a ----->|nand |--+

b ----->|_____|