A binary half-adder that takes into the state of two binary inputs (0, 1) and returns the result in the state of the two LEDs.
0 and 0 result in both LEDs turned off.
1 and 0 result in the top LED turned on.
0 and 1 result in the top LED turned on.
1 and 1 result in both LEDs turned on.
The XOR gate is the sum.
The AND gate is the carry.
