If you can show you have at least the most basic CS understanding then you show that you’re capable of adapting to new requirements on the job.You should absolutely expect to know how to traverse a tree on a coding interview! Why after the the first time did you not go home and learn it?

This is a very shortsighted opinion, and it’s one of the reasons why Google engineers are great at solving complex problems, but terrible at creating clean, reusable code or decent UX.

Just look at protobuf…