This method adds a comparable object to a binary tree. Can anyone tell me what I am doing wrong in this code:
<code>
public void add (Comparable x) throws DuplicateException
{
int diff;
BST node= this;
while (node.root != null)
{
if ((diff = x.compareTo (root)) < 0)
node= node.left;

else if (diff > 0)
node= node.right;

else
throw new DuplicateException ("Duplicate value " + x);
}
node.root= x;
node.left= new BST();
node.right= new BST();
size++;
}
</code>

torch: ~/2110/a3$ java BST ape bat cat
ape
false


while correct output should be:
ape bat cat
false

thanks in advance

here is your fault; each time you do it (without test).

A remark : never do this : BST node =this; ///This is just confusing for nothing as you can use this instead so this.root, this.left...

I tried putting a test on it ==>

if (node.root == null) {
root= x;
node.left= new BST();
node.right= new BST();
}
it still doesnt work. What kind of a test should i put on there? Thanks for your response

Normaly, for this kind of things you use recursivity and a more object oriented approach.

Anyway, I missed something, sorry.
the problem is that you have written x.compareTo(root) and not x.compareTo(node.root)

We were asked to convert a recursive method into a non-recursive one. I did what you said and it still doesnt help. It is object oriented... just a different way of solving the same problem. I am still not getting correct output and also,

node.root= x;
node.left= new BST();
node.right= new BST();
size++;

has to be done each time without test because thats where you actually add the comparable. If you note closely, you dont add comparable anywhere else.

if ((diff = x.compareTo (root)) < 0)

is used to determine which side of tree we have to add the object in- and those four lines (above) actually add comparable x at the right position. Got any other ideas

You want to know which side of the node not of the tree (I mean side of the subtree starting at node)
so it is x.compareTo(node.root)

Turns out there was nothing wrong with my code to start with. It was the toString() method that was acting up. Also, I have to increment the size inside the while loop too. By side of tree i meant the subtree.. thanks anyways