Solve the 8-Puzzle-Problem using manhattan heuristic and A* tree search.

Configuration        Goal_1            Goal_2

  7 | 2 | 4           | 1 | 2         1 | 2 | 3
  ---------         ---------         ---------
  5 |   | 6         3 | 4 | 5         4 | 5 | 6
  ---------         ---------         ---------
  8 | 3 | 1         6 | 7 | 8         7 | 8 | 

I implemented the search with Goal_1 as the desired Goal-Configuration. As i later foud out, Goal_2 is very wide spread as the Goal-Configuration.

The following table contains the data i was interested in when developing this program. I used the configuration above to test both goal-configurations. (21.11.2022)

*the total nodes are all nodes that have been added to the tree. This includes the ones that have been explored, and the ones that have not been explored yet.

To use the program type

python3 8puzzle.py [goal_config] [custom_starting_configuration]

into your terminal.

Not optional. This describes the goal-configuration you want the solver to solve for. This parameter can either be 1 or 2. 1 correspondes to Goal_1 and 2 correspondes to Goal_2, as described in the benchmark configuration.

Optional. Allows you to provide a custom starting configuration, a board you want to solve. Provide the numbers from 0-8 in the order you want your board to be. The 0 correspondes to the empty field. Every 3 numbers, a new row on the board begins. Notice, that a configuration that is impossible to solve (depending on the goal-confiuration) keeps the program searching until it eventually explores all possible nodes - that however might take a while.

python3 8puzzle.py 1 724506831

runs the solver with Goal_1 as the goal-configuration and starting configuration used as the benchmark configuration.