class Solution: def lowestCommonAncestor(self, root: 'TreeNode', p: 'TreeNode', q: 'TreeNode') -> 'TreeNode': if p.val<root.val and q.val<root.val: return self.lowestCommonAncestor(root.left,p,q) elif p.val>root.val and q.val>root.val: return self.lowestCommonAncestor(root.right,p,q) return root