This program currently provides an envoronment for runnning a sliding block puzzle for CS 380.

A profile of how many nodes are explored, how much time does the search take, and the length of the solution found is availble in output-part3 for levels 0-3. The reamining levels are not included because the algroithmntook too much time to run after level 3.

• make
• g++ compiler that supports the C++11 standard

To build, simply run

$ make

This uses g++ to compile the main script with the -std flag set to c++11.

These are the executables built that can be used to find solutions. To run any of them, use make with the first argument as the shortened name for it and an optional states file as the STATES flag. By default, the STATES flag is states/SBP-level0.txt.

$ make bfs STATE=states/SBP-level0.txt

$ make dfs STATE=states/SBP-level0.txt

$ make ids STATE=states/SBP-level0.txt

Two heuristics are provided for A*.

$ make manhattan STATE=states/SBP-level0.txt

This is the custom heuristic implemented for A*.

This heuristic works by taking the manhattan distance, and adding an extra cost if a piece is blocking the goal. If a piece is in the way of the goal, 1 is added to the cost, 0 otherwise. The reasoning behind this is that we encourage states that have no other piece blocking the goal to be searched since they may take fewer moves to find a solution. This heuristic is also admissible since the fewest possible number of moves required to reach the goal is the optimal one carried over by the manhattan distance.

$ make blockage STATE=states/SBP-level0.txt

A dry run of both A* heuristics can be performed with

$ make run

This will print how many nodes are explored, how much time does the search take, and the length of the solution found in a file called output-part3.txt. This file should already be provided in this repo. The reamining levels are not included because the algroithmntook too much time to run after level 3.