josh/gvsu
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

updated KnightsTourBoard.java

Browse Source 
git-svn-id: svn://anubis/gvsu@81 45c1a28c-8058-47b2-ae61-ca45b979098e
This commit is contained in:
josh 2008-03-26 23:27:05 +00:00
parent 51dc17a7d4
commit 5462edb8e8
1 changed files with 42 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

44
cs621/proj4/KnightsTourBoard.java
View File

@ -1,6 +1,4 @@
import java.util.Vector;
public class KnightsTourBoard
{
protected int m_width;
@ -10,5 +8,47 @@ public class KnightsTourBoard
KnightsTourBoard(int width, int height)
{
m_board = new int[width][height];
for (int x = 0; x < m_width; x++)
for (int y = 0; y < m_height; y++)
m_board[x][y] = 0;
}
public int getWidth() { return m_width; }
public int getHeight() { return m_height; }
public int getStepAt(int x, int y) { return m_board[x][y]; }
public boolean tour(int startx, int starty)
{
m_board[startx][starty] = 1;
return tourFrom(2, startx, starty);
}
private boolean tourFrom(int nextStep, int startx, int starty)
{
final int[] xoffsets = {-2, -1, 1, 2, -2, -1, 1, 2};
final int[] yoffsets = {-1, -2, -2, -1, 1, 2, 2, 1};
for (int moveIndex = 0; moveIndex < 8; moveIndex++)
{
int x = startx + xoffsets[moveIndex];
int y = starty + yoffsets[moveIndex];
if (x >= 0 && x < m_width && y >= 0 && y < m_height)
{
if (m_board[x][y] == 0) /* space has not been visited yet */
{
m_board[x][y] = nextStep; /* we just took step number
* nextStop, stop if that is all
* we needed to do */
if (nextStep == m_width * m_height)
return true;
if (tourFrom(nextStep + 1, x, y)) /* else walk from there */
return true;
m_board[x][y] = 0; /* this step did not lead to a solution */
}
}
}
return false;
}
}