The reason I personally like my question is because it's pretty close to some of the real world work we do. It's mostly mundane and easy to bang out, but really easy for someone to do a n log n solution where an n solution exists.
A good example (but not my question) would be something like
"I have a list of People objects with a `first` and `last` name. Write a function which groups together all the People with the same last name in `your language of choice`"
But much earlier they did and, apparently, these really small models still do. At this point it serves as more of a smoke test for me. Success means little, failure means a lot.