When the game starts, the numbers in the box will be upset, and what we need to do is to rearrange the numbers. But its a little difficult.
When the number is upset, the player has an open space to use. Players can slip around the numbers into this space, adjust the position, and gradually restore the number of sorting, which requires patience. The program will record the time spent by the player and the number of moves, which is convenient for the player to discover his progress.