Hi, I'm a new java user, working on a brute-force knights tour algorithm in linkedlist. The move function worked perfectly (for a while), I mean, the pointer could move forward, or backward if a wrong path was chosen. But all of a sudden, it returned me a stackoverflow error. i'm really confused, can anyone help me? (I'm pretty sure that everything else was done correctly except for the following function) I know my code is kinda tedious but since it is mostly repeating, it would not take you too long to read it. I really appreciate your help and your patience!!
p.s position1 to position8 are eight possible moves of the knight.
public void move(Node newNode)
{
System.out.println(counter);
newNode.setMove(counter);
display2();
System.out.println();
if (counter<64)
{
if (newNode.getRight()!=null&& newNode.getDown()!=null&&newNode.getDown().getDown()!=null&&newNode.isPosition1()==false&&newNode.getDown().getDown().getRight().isOccupied()==false)
{
counter++;
newNode.setPosition1(true);
newNode.getDown().getDown().getRight().setOccupied(true);
newNode.setNext(newNode.getDown().getDown().getRight());
newNode.getDown().getDown().getRight().setPrev(newNode);
move(newNode.getNext());
}
else if (newNode.getLeft()!=null&& newNode.getDown()!=null&&newNode.getDown().getDown()!=null&&newNode.isPosition2()==false&&newNode.getDown().getDown().getLeft().isOccupied()==false)
{
counter++;
newNode.setPosition2(true);
newNode.getDown().getDown().getLeft().setOccupied(true);
newNode.setNext(newNode.getDown().getDown().getLeft());
newNode.getDown().getDown().getLeft().setPrev(newNode);
move(newNode.getNext());
}
else if (newNode.getDown()!=null&&newNode.getLeft()!=null&&newNode.getLeft().getLeft()!=null&&newNode.isPosition3()==false&&newNode.getLeft().getLeft().getDown().isOccupied()==false)
{
counter++;
newNode.setPosition3(true);
newNode.getLeft().getLeft().getDown().setOccupied(true);
newNode.setNext(newNode.getLeft().getLeft().getDown());
newNode.getLeft().getLeft().getDown().setPrev(newNode);
move(newNode.getNext());
}
else if (newNode.getUp()!=null&&newNode.getLeft()!=null&&newNode.getLeft().getLeft()!=null&&newNode.isPosition4()==false&&newNode.getLeft().getLeft().getUp().isOccupied()==false)
{
counter++;
newNode.setPosition4(true);
newNode.getLeft().getLeft().getUp().setOccupied(true);
newNode.setNext(newNode.getLeft().getLeft().getUp());
newNode.getLeft().getLeft().getUp().setPrev(newNode);
move(newNode.getNext());
}
else if (newNode.getLeft()!=null&&newNode.getUp()!=null&&newNode.getUp().getUp()!=null&&newNode.isPosition5()==false&&newNode.getUp().getUp().getLeft().isOccupied()==false)
{
counter++;
newNode.setPosition5(true);
newNode.getUp().getUp().getLeft().setOccupied(true);
newNode.setNext(newNode.getUp().getUp().getLeft());
newNode.getUp().getUp().getLeft().setPrev(newNode);
move(newNode.getNext());
}
else if (newNode.getRight()!=null&&newNode.getUp()!=null&&newNode.getUp().getUp()!=null&&newNode.isPosition6()==false&&newNode.getUp().getUp().getRight().isOccupied()==false)
{
counter++;
newNode.setPosition6(true);
newNode.getUp().getUp().getRight().setOccupied(true);
newNode.setNext(newNode.getUp().getUp().getRight());
newNode.getUp().getUp().getRight().setPrev(newNode);
move(newNode.getNext());
}
else if (newNode.getUp()!=null&&newNode.getRight()!=null&&newNode.getRight().getRight()!=null&&newNode.isPosition7()==false&&newNode.getRight().getRight().getUp().isOccupied()==false)
{
counter++;
newNode.setPosition7(true);
newNode.getRight().getRight().getUp().setOccupied(true);
newNode.setNext(newNode.getRight().getRight().getUp());
newNode.getRight().getRight().getUp().setPrev(newNode);
move(newNode.getNext());
}
else if (newNode.getDown()!=null&&newNode.getRight()!=null&&newNode.getRight().getRight()!=null&&newNode.isPosition8()==false&&newNode.getRight().getRight().getDown().isOccupied()==false)
{
counter++;
newNode.setPosition8(true);
newNode.getRight().getRight().getDown().setOccupied(true);
newNode.setNext(newNode.getRight().getRight().getDown());
newNode.getRight().getRight().getDown().setPrev(newNode);
move(newNode.getNext());
}
else
{
Node node=new Node();
if (newNode.getUp()!=null)
{
newNode.getUp().setDown(node);
node.setUp(newNode.getUp());
}
if (newNode.getDown()!=null)
{
newNode.getDown().setUp(node);
node.setDown(newNode.getDown());
}
if (newNode.getRight()!=null)
{
newNode.getRight().setLeft(node);
node.setRight(newNode.getRight());
}
if (newNode.getLeft()!=null)
{
newNode.getLeft().setRight(node);
node.setLeft(newNode.getLeft());
}
counter--;
newNode.setOccupied(false);
if (newNode.getPrev()==null)
System.out.println("athis");
if (newNode.getPrev()!=null)
move(newNode.getPrev());
}
}
}
