Simple algorithm problems are things that have some connection with my work like vector clocks, detecting duplicates, traversing trees, graph search algorithms. Another type of simple algorithm problems are things that use CS fundamentals only and no ingenious tricks like manipulating trees, matrices and likewise. I can manage these problems in an interview room.

But if it is more complex than this like banker's algorithm, manipulating segment trees, finding convex hull, printing numbers on screen in some weird fashion or like that I will get stressed in the interview room. I suck at these.

The best interviews for me are those that are related to domain expertise. Like problems involving maintaining integrity of data in a distributed database, implementing partial ordering of events, designing data consistency policies.