I refuse to give these kinds of interviews. They don't really tell me much other than they know algorithms and data structures. And with thousands of articles and even whole books dedicated to passing those sorts of interviews, that's not saying much at all. What I really want to know is:

- can the candidate get the work we need to do done?

- what do they prioritise when doing the work? What do they value?

- can they do it well? In reasonable time?

- how well do they fit in with my team? Are they somebody my people want to work with? (Probably one of the most important things)

- how much will they grow? Are they open to feedback? Are they focused on getting better?

A whiteboarding session doesn't really tell me much here. But if all the answers to the above are positive, I'm sure the candidate has the flexibility to find and learn what they need to solve a problem.