That's how brain-teaser questions usually stump me - because I impose some limitation that doesn't exist. The question had pretty specific limitations, but the

That's how brain-teaser questions usually stump me - because I impose some limitation that doesn't exist. The question had pretty specific limitations, but the amount of resources wasn't one of them. To me the answer is valid. If the interviewer wanted to see an implementation of a division function they could have just said "please implement a division function"