Finding the common ancestor in a binary tree

Question

This question was asked to me in an interview: I have a binary tree and I have to find the common ancestor (parent) given two random nodes of that tree. I am also given a point

Answer 1

hi this will return lowest ancestor node value where root of tree and val1,val2 -> data values for nodes are being passed

int CommonAncestor(node *root, int val1,int val2) 
{

    if(root == NULL || (! root->left && ! root->right  )
        return false;

        while(root)
        {
            if(root->data < val1 && root->data < val2)
             {
                root = root->left;
             }
             else if(root->data > val1 && root->data > val2)
            {
                root= root->right;
            }
            else
              return root->data;      
        }
}