In one I remember one problem asked me to implement a hashmap, which wasn’t too hard, and then the second one had to do with some sort of latency prediction thing, where cleanups had to be done after certain numbers of milliseconds. I am afraid I cannot remember the details, but I remember that the second problem was quite difficult.

I suspect I could do much better now (or at least I hope I would), but I have not interviewed for them in like five years.