8 Puzzle Code - ReadMe.txt

//This program try to solve the 8-PUZZLE problem.

//Program version: Version 1
//Create date: 26 JUN 2002
//Description: Background process the solution.
1) Initial the problem first stage.
2) Expand the problem tree space from problem state to
new state.
3) This version got some bugs in expanding to new state.
4) Using Queue data structure and State Node to implement problem
tree problem space and performing breath first search algo.
5) Did not implement step by step solutions display.
6) Solution to puzzle problem is performed background.
7) Some bugs, new state didnt be generated correctly.

//Program version: Version 2
//Create date: 28 JUN 2002
//Description: 1) Enhance version 1.
2) Implement puzzle problem tree using tree data structure.
3) Create multi expanding tree using Tree and TreeNode data
structure. Implementing maximum four child per node.
4) Implementing breath first search on tree using Queue data
structure.
5) Implementing step by step solution display. Using stack to
collect the state from the bottom of tree until the root
of problem tree.
6) Limitation:
** Did not implement heuristic search technique.
** Problem is, the n number of expanded node is
3 to the power of steps for solution to a certain
question.
** Need a lot of time and memory space to solve certain
puzzle problem.

//Update 3 July 2002
1) Implement Heuristic search. Mahathan distance heuristic search.
Be able to solve certain difficult puzzle in short time.
Better than blind breath first search.

//Update 8 July 2002
1) Add a pair of previous and next button for user to step through the
solution computer get.


//Update 11 July 2002
1) Correct wrong implementation of Manhattan Distance Algorithm.
2) Implement correct Manhattan Distance Algorithm.
3) Fix some exception memory bugs.