People on both sides of the table have the common misconception that coding challenges are about solving the problem. They're not, coding challenges are there for me to gain an insight into how you think through problems and the questions you ask are 100x more important to me than the code you write.

I have a colleague who, every coding challenge, immediately started by writing a bunch of tests and asking questions around the edge cases so that he could clarify the exact specs of the task he was being asked to perform. Any interviewer who didn't roll with that was a sign to him that there probably wasn't an engineering maturity culture fit and helped eliminate a lot of companies.

The story he was trying to tell was that he was an engineer that considered understanding the problem to be a much more important task than understanding the solution and he managed to tell it via the way he approached whiteboard coding.