Im stuck in this project of mine, reason being is that I haven\'t wrriten any co
ID: 3561448 • Letter: I
Question
Im stuck in this project of mine, reason being is that I haven't wrriten any code for about 2 years. Please include plenty of comments.
There is a famous puzzle called the 15-puzzle (feel free to look it up on the internet - eg en.wikipedia.org/wiki/15 puzzle). In this puzzle there is a frame that could hold 16 tiles in a 4x4 configuration, but the frame contains only 15 tiles where each tile is labeled with a number between 1 and 15. Since one of the locations is empty, it is possible to slide another tile (from above/below/right/left of the empty location) into this location. The goal of the puzzle is to reach the point where the numbers are organized so that they read (top to bottom, left to right) 1, 2, 3, . . . , 15, space. The diagram below shows a very simple example with the final solution on the right.
You will be writing a Java program to allow people to play the 24-puzzle (the obvious variant where the frame is 5x5) puzzle) in a text based context.
Requirements: To complete this project you will write two classes.
Create a file called Board.java which will be the
Explanation / Answer
class SlidePuzzleModel {
private static final int ROWS = 5;
private static final int COLS = 5;
private Tile[][] _contents; // All tiles.
private Tile _emptyTile; // The empty space.
//================================================= constructor
public SlidePuzzleModel() {
_contents = new Tile[ROWS][COLS];
reset(); // Initialize and shuffle tiles.
}//end constructor
//===================================================== getFace
// Return the string to display at given row, col.
String getFace(int row, int col) {
return _contents[row][col].getFace();
}//end getFace
//======================================================= reset
// Initialize and shuffle the tiles.
public void reset() {
for (int r=0; r<ROWS; r++) {
for (int c=0; c<COLS; c++) {
_contents[r][c] = new Tile(r, c, "" + (r*COLS+c+1));
}
}
//--- Set last tile face to null to mark empty space
_emptyTile = _contents[ROWS-1][COLS-1];
_emptyTile.setFace(null);
//-- Shuffle - Exchange each tile with random tile.
for (int r=0; r<ROWS; r++) {
for (int c=0; c<COLS; c++) {
exchangeTiles(r, c, (int)(Math.random()*ROWS)
, (int)(Math.random()*COLS));
}
}
}//end reset
//==================================================== moveTile
// Move a tile to empty position beside it, if possible.
// Return true if it was moved, false if not legal.
public boolean moveTile(int r, int c) {
//--- It's a legal move if the empty cell is next to it.
return checkEmpty(r, c, -1, 0) || checkEmpty(r, c, 1, 0)
|| checkEmpty(r, c, 0, -1) || checkEmpty(r, c, 0, 1);
}//end moveTile
//================================================== checkEmpty
// Check to see if there is an empty position beside tile.
// Return true and exchange if possible, else return false.
private boolean checkEmpty(int r, int c, int rdelta, int cdelta) {
int rNeighbor = r + rdelta;
int cNeighbor = c + cdelta;
//--- Check to see if this neighbor is on board and is empty.
if (isLegalRowCol(rNeighbor, cNeighbor)
&& _contents[rNeighbor][cNeighbor] == _emptyTile) {
exchangeTiles(r, c, rNeighbor, cNeighbor);
return true;
}
return false;
}//end checkEmpty
//=============================================== isLegalRowCol
// Check for legal row, col
public boolean isLegalRowCol(int r, int c) {
return r>=0 && r<ROWS && c>=0 && c<COLS;
}//end isLegalRowCol
//=============================================== exchangeTiles
// Exchange two tiles.
private void exchangeTiles(int r1, int c1, int r2, int c2) {
Tile temp = _contents[r1][c1];
_contents[r1][c1] = _contents[r2][c2];
_contents[r2][c2] = temp;
}//end exchangeTiles
//=================================================== isGameOver
public boolean isGameOver() {
for (int r=0; r<ROWS; r++) {
for (int c=0; c<ROWS; c++) {
Tile trc = _contents[r][c];
return trc.isInFinalPosition(r, c);
}
}
//--- Falling thru loop means nothing out of place.
return true;
}//end isGameOver
}//end class SlidePuzzleModel
////////////////////////////////////////////////////////// class Tile
// Represents the individual "tiles" that slide in puzzle.
class Tile {
//============================================ instance variables
private int _row; // row of final position
private int _col; // col of final position
private String _face; // string to display
//end instance variables
//==================================================== constructor
public Tile(int row, int col, String face) {
_row = row;
_col = col;
_face = face;
}//end constructor
//======================================================== setFace
public void setFace(String newFace) {
_face = newFace;
}//end getFace
//======================================================== getFace
public String getFace() {
return _face;
}//end getFace
//=============================================== isInFinalPosition
public boolean isInFinalPosition(int r, int c) {
return r==_row && c==_col;
}//end isInFinalPosition
}//end class Tile