||I'm glad you doubt me. From the other responses, I was starting to think maybe I had just set the bar too high or something and that I was wrong to be disappointed.
To be clear, I am in full agreement with you - I have no idea how you can get through a CS degree and not be able to solve that problem while holding your breath. And, to be clear, the bulk of the applicants were technical school grads, but there were some with CS degrees.
I guess the reason I wasn't more surprised is that this isn't our first attempt at this kind of thing. We'd previously done "on your own time" challenges with mazes and such - and got back either horrible, lengthy, non-solutions that barely passed the example (or just "that's too hard" or "I don't have time for that"). So while I made this challenge as easy as I could, in the back of my mind I kind of expected it to give people problems. I just didn't expect it to give an hour's worth of problems to so many people.
EDIT: here's the previous challenge we asked people to do a few years ago (before I was much involved in TopCoder - so I apologize for the ambiguous problem): here. The guy who turned in the only strong solution on this one is my office neighbour now.