Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. Note that you will lose points if you ask for hints!

CARRY IN input A input B CARRY OUT SUM digit 0 0 0 0 0 0 1 0 0 1 0 0 1 0 1 1 0 1 0 0 1 0 1 1 1 1 0 1 0 1 1 1 1