[digitallogic]

I had an advanced algorithms professor who was brilliant but not always put together. Eg - he didn't always dress himself correctly. Think, two different shoes or a button shirt mis-buttoned so there was an extra hole at the top.

He came in one day and wrote this problem on the board, and asked if anyone could solve it in O(n log n). No one did, he seemed really disappointed. The TA came in afterwards, and someone asked why we were going over this specific problem. Would it be on the final? The TA said "You professor gave you this problem because he went to a conference recently, and this was announced to great fanfare as a new unsolved problem. For the last two weeks, he's been asking anyone who will listen if they can solve this problem."