Depends on what you're looking for. Does it work is the most important thing by a mile but if you've asked them to wrie production ready code then you've got t

Depends on what you're looking for. Does it work is the most important thing by a mile but if you've asked them to wrie production ready code then you've got to ask "how would I feel if one of my developers checked this into version control and how would it fair in a code review?" Maintainability, readability, efficiency and most significantly the candidates ability to explain why they took the approach they did. I wouldn't hold any approach against someone so long as they could talk intelligently about the trade offs and why they'd done what they'd done. Even really simple problems are a chance to see whether someone thinks about things.