Data structure questions heavily favors previous use. For example in the past I've used a multi-dictionary for certain problems, so it would have been an easy r

Data structure questions heavily favors previous use. For example in the past I've used a multi-dictionary for certain problems, so it would have been an easy reach for me; but maybe not for someone from a different coding history. Personally I prefer something like fizzbuzz which is a pure code question, it applies to candidates of all levels and tells you if they can reason through problems.