Back in the spring of 2005, after having graduating from college, I went looking for a job. I got the chance to interview for Microsoft, though I’m not sure what I would have ended up doing had I gotten the job (they never really told me). My interview was conducted entirely over the phone, and consisted of the typical “brain teaser” type questions that Microsoft is famous for. Needless to say, I performed very poorly and was instantly rejected. The guy on the phone said he’d let me know and, 10 minutes later via email, I knew.
One of the questions they asked me stumped me beyond belief, and I butchered my answer terribly. Not only was I embarrassed for myself, I was embarrassed for the interviewer, having to patiently listen to me. 😳 Anyway, here’s a retelling of the question I was asked:
Given a large NxN tic-tac-toe board (instead of the regular 3×3 board), design a function to determine whether any player is winning in the current round, given the current board state.
I realize now that I misinterpreted the question horribly. The interviewer stated the question quite differently than I have it written above; I believe he used something along the lines of “given a tic-tac-toe board of N dimensions …” I assumed that the bit about dimensionality meant delving into the realm of 3 or more physical dimensions; essentially something like 3-D tic-tac-toe. Obviously, solving such a problem is much more difficult than solving on an NxN 2-D board.
Tonight, for whatever reason, I recalled this question and the fact that I never found an answer for myself. Happily, I subsequently stumbled upon someone else’s answer (see question 4), which is quite clever. It’s good to finally resolve this problem.
I know interviewing candidates for a job can be tricky, but asking these kinds of questions is silly. Does someone’s ability to answer this kind of question really prove they are a better programmer than someone who can’t? In the end, I’m eternally glad I didn’t get hired for Microsoft; I now realize they are one of the companies I would least like to work for. My current employer seemed much more concerned with real-world problems, my previous employment experience, and the (increasingly rare) ability to program in C++. For that, I am oh-so-grateful.