@[TOC]慕课《数据结构与算法python版》第三周编程作业 有效的括号 题目要求 脚本 def isValid(s): dic = {'(': ')', '[': ']', '{': '}'} stack = [] for i in s: if i in dic.keys(): stack.append(i) elif i in dic.values(): if len(stack) == 0 or dic.get(stack[-1]) != i: re