Exactly this. I remember there were 5-6 problems they had: Gamblor, Prime Bits, SuperPatterns, a Unicode problem, and perhaps another graph related one. I managed to finish maybe four of them in my spare time at college, and wasn't too excited about working for Facebook. At the time I thought it was just a poor substitute for MySpace, which I didn't have much respect for anyway, and that it was technologically uninteresting. So, I never sent them in.

I wonder how fb engineers hired (c) 2005 are doing.