Implement knight's tour [Wirth, 1976, p. 137] in Java using the Ba c kt rack class and its associated Ba c kt ra c ke r intc1face. Note that the smallest chess board (greater than 1) for which a solution exists is 5 x 5; verify this. Given is an x n board. A knight-allowed to move according to the rules of chess-is placed on the board with initial coordinates (xo, Yo). The problem is to find a covering of the entire board, if there exists one, that is, to compute a tour of n2 - 1 moves such that every square of the board is visited exactly once.