public class PegSolitaireBoard $\{$

protected char$[][]$ pegBoard;

private static final int UP $=1$;

private static final int DOWN $=2$;

private static final int RIGHT $=3$;

private static final int LEFT $=4$;

$//$ Initializes the board at its starting position

$//[\text{'}\text{'},\text{'}\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}\text{'},\text{'}\text{'}],$

$//[\text{'}\text{'},\text{'}\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}\text{'},\text{'}\text{'}],$

$//[\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'}],$

$//[\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$O$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'}],$

$//[\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'}],$

$//[\text{'}\text{'},\text{'}\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}\text{'},\text{'}\text{'}],$

$//[\text{'}\text{'},\text{'}\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}$X$\text{'},\text{'}\text{'},\text{'}\text{'}]$

public PegSolitaireBoard$()\{$

this.pegBoard $=$ new char$[7][7]$;

for $($int i $=0$; i $<7$; i$++)\{$

for $($int j $=0$; j $<7$; j$++)\{$

if $($i $<2$ && j $<2)\{$

this.pegBoard$[$i$][$j$]=\text{'}\text{'}$;

$\}$ else if $($i $<2$ && j $>4)\{$

this.pegBoard$[$i$][$j$]=\text{'}\text{'}$;

$\}$ else if $($i $>4$ && j $<2)\{$

this.pegBoard$[$i$][$j$]=\text{'}\text{'}$;

$\}$ else if $($i $>4$ && j $>4)\{$

this.pegBoard$[$i$][$j$]=\text{'}\text{'}$;

$\}$ else if $($i $==3$ && j $==3)\{$

this.pegBoard$[$i$][$j$]=\text{'}$O$\text{'}$;

$\}$ else $\{$

this.pegBoard$[$i$][$j$]=\text{'}$X$\text{'}$;

$\}$

$\}$

$\}$

$\}$

private boolean moveForward$($int x$,$ int y$,$ int direction$)\{$

$//$ Implement moveForward here

int newX $=$ getNewX$($x$,$ direction$)$;

int newY $=$ getNewY$($y$,$ direction$)$;

if $($checkMove$($x$,$ y$,$ newX, newY$)$ && pegBoard$[$newX$][$newY$]==\text{'}$X$\text{'}$ && pegBoard$[$x$][$y$]==\text{'}$O$\text{'})\{$

System.out.println$("***********$ ADD $***********")$;

System.out.println$("$from $("+$ newX $+","+$ newY $+")$ to $("+$ x $+","+$ y $+")")$;

addPeg$($x$,$ y$)$;

removePeg$(($newX $+$ x$)/2,($newY $+$ y$)/2)$;

removePeg$($newX$,$ newY$)$;

print$()$;

System.out.println$("***********$ ADD END $***********$

$")$;

return true;

$\}$

return false;

$\}$

$//$ moves the $\text{'}$X$\text{'}$s and $\text{'}$O$\text{'}$s back to their initial position before the jump

$//$ occurred

private void moveBackward$($int x$,$ int y$,$ int direction$)\{$

$//$ Implement moveBackward here

int newX $=$ getNewX$($x$,$ direction$)$;

int newY $=$ getNewY$($y$,$ direction$)$;

int midX $=($newX $+$ x$)/2$;

int midY $=($newY $+$ y$)/2$;

$//$ if $($newX $<0||$ newX $>=7||$ newY $<0||$ newY $>=7)\{$

$//\}$

System.out.println$("***********$ UNDO $***********")$;

System.out.println$("$undo from $("+$ newX $+","+$ newY $+")$ to $("+$ x $+","+$ y $+")")$;

print$()$;

addPeg$($newX$,$ newY$)$;

addPeg$($midX$,$ midY$)$;

removePeg$($x$,$ y$)$;

print$()$;

System.out.println$("***********$ UNDO END $***********$

$")$;

$\}$

private void addPeg$($int x$,$ int y$)\{$

pegBoard$[$x$][$y$]=\text{'}$X$\text{'}$;

$\}$

private void removePeg$($int x$,$ int y$)\{$

pegBoard$[$x$][$y$]=\text{'}$O$\text{'}$;

$\}$

private boolean checkMove$($int x$,$ int y$,$ int newX, int newY$)\{$

$//$ Implement checkMove here

$//$ checks if the result of the jump will be out of bounds

if $($newX $<0||$ newX $>=7||$ newY $<0||$ newY $>=7)\{$

return false;

$\}$

$//$ checks that the $\text{'}$X$\text{'}$ performing the jump has one more $\text{'}$X$\text{'}$ in between itself

int midX $=($x $+$ newX$)/2$;

int midY $=($y $+$ newY$)/2$;

if $($pegBoard$[$midX$][$midY$]!=\text{'}$X$\text{'}||$ pegBoard$[$newX$][$newY$]==\text{'}\text{'})\{$

return false;

$\}$

return true;

$\}$

private boolean isValidMove$($int x$,$ int y$,$ int direction$)\{$

int newX $=$ getNewX$($x$,$ direction$)$;

int newY $=$ getNewY$($y$,$ direction$)$;

return checkMove$($x$,$ y$,$ newX, newY$)$ && pegBoard$[$newX$][$newY$]==\text{'}$O$\text{'}$ && pegBoard$[$x$][$y$]==\text{'}$X$\text{'}$;

$\}$

private int getNewX$($int x$,$ int direction$)\{$

int newX $=$ x;

switch $($direction$)\{$

case RIGHT:

newX $=$ newX $+2$;

break;

case LEFT:

newX $=$ newX $-2$;

$\}$

return newX;

$\}$

private int getNewY$($int y$,$ int direction$)\{$

int newY $=$ y;

switch $($direction$)\{$

case UP:

newY $=$ newY $+2$;

break;

case DOWN:

newY $=$ newY $-2$;

$\}$

return newY;

$\}$

private void print$()\{$

for $($char$[]$ row : pegBoard$)\{$

for $($char cell : row$)\{$

System.out.print$($cell $+"")$;

$\}$

System.out.println$()$;

$\}$

System.out.println$()$;

$\}$

public boolean findSolution$($int move$)\{$

if $($move $==32$ && pegBoard$[3][3]==\text{'}$X$\text{'})\{$

System.out.println$("$Done$!")$;

print$()$;

return true;

$\}$ else $\{$

for $($int horizontal $=0$; horizontal $<$ pegBoard.length; horizontal$++)\{$

for $($int vertical $=0$; vertical $<$ pegBoard.length; vertical$++)\{$

int x $=$ vertical;