single parent nodes

[DocCeaser]

I'm trying to count the number of single parent nodes in this binary tree.
When I run my program it always returns 1. What am I doing wrong?

int binaryTreeType::singleParent(binaryTreeNode *p)
{   
	if(p==NULL)
		return 0;
	else
	{
			if (p->llink == NULL && p->rlink != NULL)
				return 1 + singleParent(p->rlink);
			else if(p->rlink == NULL && p->llink != NULL)
				return 1 + singleParent(p->llink);
			else
				return singleParent(p->llink);
}
}

[Zhuge]

I don't think you are handling all cases there. What if both children are null pointers? Then the else clause will fail. In the case where they are both non-null, you'll probably also want to sum the singeParent() results for each, rather than just the left side. Not sure if this will fix your problem though.

[DocCeaser]

Thanks for the idea. I'll see what happens.