on your video, the way you made the ALU made it so if you were to subtract 0 from 0 it would say that the answer is 0 but it would also make the carry output true. here's my fixed ALU, which does not have this problem:
on your video, the way you made the ALU made it so if you were to subtract 0 from 0 it would say that the answer is 0 but it would also make the carry output true. here's my fixed ALU, which does not have this problem: