I have been preparing for an Amazon onsite in the near future, and despite my years of programming professonally and all my schooling, I can't seem to wrap my head around answering simple problem solving questions.

I can get it intuitively, but then freeze and start messing up when doing edge cases or just implementing what I'm doing on paper.

Does anyone have any recommendations on how to think about these problems? Maybe some resources I could study? I'd really appreciate any help on this.