I had an on-site interview a few years ago but didn't get an offer at that time. Recently, an internal recruiter contacted me to ask if I was interested in a Software Engineer position. He immediately scheduled a phone screening, even though I had an on-site interview once before.

The interviewer was from a completely different job and questioned me with a lot of irrelevant questions. Although I did write the correct code for his question, he didn't seem to like me for some reasons.

I wasn't invited for an on-site this time, even though I'm well-qualified. Google's hiring process has a really high false negative rate.

The recruiter apologized for the outcome but wasn't able to do anything once the decision was made by the engineering team. I have to wait for another few years until I can re-apply.

Search for the smallest value in a tree. What if you have enough memory? How can you improve the speed?