15 puzzle

15 puzzle
This is a famous game on a beautiful background of a night city.
The number in the title game "15 puzzle" is set on the number of cells. Each cell is numbered. One of the cells is empty. The player can move the cells through an empty cell. Goal of the game "15 puzzle" - moving the cells in a board to achieve a ordering of numbers in ascending order, it is desirable to making as little as possible moves.
Cells move by pressing.
The game has three difficulty levels: 3 x 3, 4 x 4 and 5 x 5.