A simple solver for the puzzle game Rush Hour.
This code is intended to be a straightforward implementation of a breadth-first search to exhaustively solve a puzzle. It might hopefully be useful to somebody learning about basic AI methods. I tried to comment my code well and make it easy to read and not do too many "weird" things. Rush Hour is a particular good puzzle to use as an example for understanding the basic principle of exploring the state space of a game because the size of the search space is relatively constrained. The board is relatively small, and in any given board position, there are only a few cars on the board that are able to move.
See the top of main() for now to get different boards into the input. Since you have the code, the easiest thing is probably just to hardcode one. There are three examples from the game included. Just comment in the appropriate one. We use the same basic format for describing the board as the cards do that come with the game.
You can learn a great deal about how the code "thinks" thorugh the problem by modifying the code to set DEBUG_PROGRESS_OUTPUT=true.
I hope you find the code interesting and useful.