// Check if given data is present in given node or not
    bool search(Node *root, int data)
    {
        while(root != nullptr)
        {
            if(root->data == data)
            {
                return true;
            }
            else if(data < root->data)
            {
                root = root->left;
            }
            else
            {
                root = root->right;
            }
        }
        return false;
    }
  
    Node *lca(Node *root, int v1,int v2) {
		stack<Node*> s;
        Node *temp = root;
        
        // searching for v1 and storing its path in stack
        while(temp != nullptr)
        {
            s.push(temp);
            if(temp->data == v1)
            {
                break;
            }
            else if(v1 < temp->data)
            {
                temp = temp->left;
            }
            else
            {
                temp = temp->right;
            }
        }
        // search complete

        // search for v2 in each ancestor of v1
        while(!s.empty())
        {
            if(search(s.top(), v2))
            {
                Node *ans = s.top();
                return ans;
            }
            s.pop();
        }
        
        return nullptr;
        
    }