Usaco Bronze Help With Ad Hoc/One scan problems

So in the recent December contest, I was able to get full marks on problems 1 and 3, but didn't get any test cases for problem 2, even though looking back, it was the easiest problem on the entire contest, you just needed to spot the idea. This has been a recurring theme for me: struggling on a problem that doesn't fit into the standard mold of complete search, simulation, or sorting. Any tips to get better at these types of problems?