Multiplying 2-bit by 2-bit.

Check out my last entry on a full-adder: https://ldjam.com/events/ludum-dare/46/tyson-lee-keep-it-alive-edition/the-full-adder

Come tinker and play at: https://ldjam.com/events/ludum-dare/46/tyson-lee-keep-it-alive-edition