Knight’s Tour
Chess is played on an 8-by-8 board.
A knight can move 2 in one direction (horizontal or vertical) and 1 in the other direction (vertical or horizontal). For example, Kn can move to each square marked X.
Problem. Write a program that tries to find a "knight's tour", e.g., starting in the upper left corner, the knight visits each of the 64 squares exactly once.