There’s plenty of strategies. In this case, if you can see two code based behaviors have diverged, just run both through a step by step debugger and see where

There’s plenty of strategies. In this case, if you can see two code based behaviors have diverged, just run both through a step by step debugger and see where they diverge. Or if you run both through a profiler, you can see what segment of code is taking a crazy amount of time in comparison. In general, narrowing down what you’re looking at is the goal. In this case, a big hint is that the code should be O(nlogn) but is actually O(n^2) which is a huge hint that we’re in a nested loop and the break condition isn’t getting triggered properly. I would have looked closely at the loops because of this. The code itself is ~400 lines long minus a bunch of comments. This feels very approachable to skim through in an hour. I also love creating new variables and naming them what I’m learning. Often times naming things will make bugs very obvious.