Please help! Implement 4-bit Incrementer with two 74LS163 + 74LS74A + XNOR gate(s) + AND gate(s)
The hint is important. You'll have two counters. One gets loaded with "A". What do you load into the other one so that it can tell you when you've incremented the first counter by the right number of cycles?

They're trying to get you to think in terms of state machines. This one is a bit complicated, because there are three state machines involved &mdash; the two counters, plus some sort of sequencer that controls the overall operation. Draw yourself some state diagrams that show what needs to happen and in what order.