10 . LCA of binary tree

TreeNode <int>* helper(TreeNode<int> *root, int x, int y)
{
    if(root == NULL)
    {
        return NULL ; 
    }
    if(root->data == x )
    {
        return root ; 
    }
    if(root->data == y )
    {
        return root ; 
    }
    TreeNode <int> * l = helper(root->left  , x, y) ;
    TreeNode <int> * r = helper(root->right , x, y) ; 
    if(l == NULL)
    {
        return r ; 
    }
      if(r == NULL)
    {
        return l; 
      }
    return root ; 
    
   
}
int lowestCommonAncestor(TreeNode<int> *root, int x, int y)
{
    return helper(root , x, y)->data  ;
	//    Write your code here
}