I didn't intentionally put the array there, they were there when I took the logic gates from a save that I have, that has all the necessary parts (Instead of remaking them every time I needed one) and they came with array, because when i needed them it was necessary. The first input is A, the second is B and the third is Cin. It is supposed to calculate more digits, if you connect the Cin to the Cout, but it didn't work very well. It only worked to allow one more Full adder.
I can't figure out how to expand its capabilities (numbers greater than three as a sum). I used a diagram of a circuit to create this, however when combining them (as is shown in other diagrams) It just doesn't do anything about the third binary didit (will only calculate up to 3 (11) ). Any ideas?