Thanks for the feedback! I've spent a lot of time trying to add tests but ran into a ton of problems trying to get Jest's useFakeTimers and promises to play we

Thanks for the feedback! I've spent a lot of time trying to add tests but ran into a ton of problems trying to get Jest's useFakeTimers and promises to play well together. I will take another crack at to see if I can work around the problems this time. Not sure I understand what you mean by returning the promise directly? Could you explain a bit more why using sets or linked lists would help with efficiency here? Thanks I'll check out your playlist!