Horses walk in turn
Translate each of the two knights from one square to another using the fewest total number of moves.
The two knights cannot occupy the same square at the same time. Moves must alternate between the knights.
Input
The input file provides the starting coordinates for the first and second knight, followed by the target coordinates for each knight.
Output
The program should output the sequence of moves for the knights, with each move on a separate line. Each line should start with the knight's number (1 or 2), followed by the coordinates of the square to which it moves, separated by a space. You should provide any one of the possible optimal solutions. The knights must move in turns, and either knight can move first. The number of moves each knight makes may differ.