Arrange the tiles so that all the tiles are in the correct positions. You do this by moving tiles.  You can move a tile up, down, left, or right, so long as the following conditions are met:
A) there's no other tile blocking you in the direction of the movement; and B) you're not trying to move outside of the boundaries/edges.  If you wish to try another picture, try this.


The 8-puzzle - also known as the sliding-block/tile-puzzle - is one of the most popular instrument in the artificial intelligence (AI) studies. It belongs to AI exercises commonly referred as toy-problems.

Toy problems - as the name implies - are somewhat fun.  They are not real-world problems, but they're useful because they are simple to define and confined.  It means that an exact description of the problems are possible, and all the factors that affects the problem are known (there is no need to worry about unpredictable factors such as weather or terrain).

The 8-puzzle, along with chess, tic-tac-toe, and backgammon, has been used to study new search algorithms, neural-network, and  path-finding.  It's usually one of the first instrument that computer-scientists use to test a new search algorithm.

About the Applet

This applet implements the A* search (pronounced A-star) algorithm to find solutions.  It may take a while for the applet to find a solution.  If you become impatient, reshuffle and try another puzzle.
The SOLUTION button will be enabled only after you ask the computer to solve the puzzle for you.

This Java applet is Copyright 1997, 1998 F. Permadi
Programmed by F. Permadi

This applet is copyrighted and may not be used/placed on other websites. 
This applet may not be distributed in any medium without express
written permission from the author.