Exactly. As an interviewer I don't get any data if you have an algorithm memorized and throw it on the board. I'm trying to assess critical thinking and problem

Exactly. As an interviewer I don't get any data if you have an algorithm memorized and throw it on the board. I'm trying to assess critical thinking and problem-solving skills, I've voted to hire many people who clearly had never seen the problem before, didn't get a working solution in the time we had, but demonstrated great problem-solving approach.