{ { 1st digit - A 2nd digit - B 3rd digit - Cin (carry in) } - inputs, { 1st digit - Cout (carry out} 2nd digit - Sum } - outputs} Truth table - 000 - 00 001 - 01 010 - 01 100 - 01 011 - 10 110 - 10 101 - 10 111 - 11