I had a brief HR call, followed by a technical Hangouts interview 10 days later.

I fumbled with the problem a bit but came up with the algorithm after a few unsolicited hints. It went smoothly from there.

I quickly wrote the implementation, and then we went through the code line-by-line with a test case to verify it. The interviewer seemed happy with it.

After a few days and four emails from the recruiter, I finally got a phone call informing me that my solution wasn't good enough.

When I asked for more detailed feedback, I was told that my algorithm was good, but I had difficulty translating it into code without help. As a result, I didn't get far enough.

I'd prefer an automated rejection email over such nonsense.

Find the greatest element in a binary search tree that is less than or equal to a target value.