#!/usr/bin/env python3 # -*- coding: utf-8 -*- # author: bt3gl def count_unival(root) -> int: global count = 0 def dfs(node): if node is None: return True if dfs(node.left) and dfs(node.right): if (node.left and node.left.val != node.val) or \ (node.right and node.right.val != node.val): return False self.count += 1 return True return False dfs(root) return count