Variations of this riddle appear on the net from time to time. It is sometimes attributed to Albert Einstein and it is claimed that 98% of the people are incapable of solving it. Some commentators suggest that Einstein created such puzzles not to test out intelligence but to get rid of all the students who wanted him as an advisor. It is not likely that there is any truth to these stories. Wherever this comes from, it is a nice riddle.

Try to solve the puzzle and find out whether you belong to the 2% of the smartest people on Earth!

This lite version of the game is fully functional except that the game is not saved when you exit.