Knight Minimum Moves

The task is to determine the minimum number of moves required for a knight on a chessboard of size N × N to travel from a given start position to a target position. The knight moves in an 'L'-shape: two cells in one direction and one cell in the perpendicular direction.

If the knight cannot reach the target position, the answer should be -1. Note that if the starting position is the same as the target position, no moves are required (output 0).

This problem can be effectively solved by a breadth-first search (BFS) algorithm on the chessboard.

inputFormat

The input is read from standard input (stdin). It consists of three lines:

• The first line contains an integer N representing the size of the chessboard (which is N × N).
• The second line contains two space-separated integers representing the starting position coordinates.
• The third line contains two space-separated integers representing the target position coordinates.

All positions use 0-indexing.

outputFormat

The output is a single integer printed to standard output (stdout), representing the minimum number of moves required for the knight to reach the target position, or -1 if it is not reachable.

8
0 0
7 7

6