Difficulty :

15 squares numbered from 1 to 15 are placed in a 4x4 box leaving one position out of the 16 empty. Using the empty square you can move the other squares, the goal being to reposition the squares from a given arbitrary starting arrangement to an increasing order (1 to 15 from top left to bottom right). You just have to click on a square (neighbor to the empty square) to move it to the empty square.

New game

Number of moves :

Game strategy