Given a string S of '(' and ')' parentheses, we add the minimum number of parentheses ( '(' or ')', and in any positions ) so that the resulting parentheses string is valid. Formally, a parentheses string is valid if and only if: It is the empty stri…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 目录 题目描述 题目大意 解题方法 日期 题目地址: https://leetcode.com/problems/minimum-add-to-make-parentheses-valid/ 题目描述 Given a string S of '(' and ')' parentheses, we add the minimum number of parentheses ( '(' o…

题目如下: 解题思路:上周都在忙着参加CTF,没时间做题,今天来更新一下博客吧.括号问题在leetcode中出现了很多,本题的解题思路和以前的括号问题一样,使用栈.遍历Input,如果是'('直接入栈:如果是')'则判断栈顶是否为'(',如果栈顶是'(',栈顶元素出栈,否则要加括号的count加1.遍历完成后,count + 栈里剩余的 '(' 的数量就是结果. 代码如下: class Solution(object): def minAddToMakeValid(self, S): "&quo…

Given a string S of '(' and ')' parentheses, we add the minimum number of parentheses ( '(' or ')', and in any positions ) so that the resulting parentheses string is valid. Formally, a parentheses string is valid if and only if: It is the empty stri…

921. 使括号有效的最少添加 921. Minimum Add to Make Parentheses Valid 题目描述 给定一个由 '(' 和 ')' 括号组成的字符串 S,我们需要添加最少的括号( '(' 或是 ')',可以在任何位置),以使得到的括号字符串有效. 从形式上讲,只有满足下面几点之一,括号字符串才是有效的: 它是一个空字符串,或者 它可以被写成 AB (A 与 B 连接),其中 A 和 B 都是有效字符串,或者 它可以被写作 (A),其中 A 是有效字符串. 给定一个括号…

Given a string S of '(' and ')' parentheses, we add the minimum number of parentheses ( '(' or ')', and in any positions ) so that the resulting parentheses string is valid. Formally, a parentheses string is valid if and only if: It is the empty stri…

Given a string S of '(' and ')' parentheses, we add the minimum number of parentheses ( '(' or ')', and in any positions ) so that the resulting parentheses string is valid. Formally, a parentheses string is valid if and only if: It is the empty stri…

原题链接在这里:https://leetcode.com/problems/minimum-remove-to-make-valid-parentheses/ 题目: Given a string s of '(' , ')' and lowercase English characters. Your task is to remove the minimum number of parentheses ( '(' or ')', in any positions ) so that the…

[LeetCode]Minimum Depth of Binary Tree Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 递归和非递归,此提比较简单.广度优先遍历即可.关键之处就在于如何保持访问深度. 下面是4种代码: im…

leetcode面试准备:Add and Search Word - Data structure design 1 题目 Design a data structure that supports the following two operations: void addWord(word) bool search(word) search(word) can search a literal word or a regular expression string containing on…