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…
class Solution: def minAddToMakeValid(self, S): """ :type S: str :rtype: int """ stack = [] S = list(S) for s in S: if len(stack) != 0: if s == ")" and stack[-1] == "(": stack.pop() else: stack.append(s) e…
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…
Redundant Paths Time Limit: 1000MS Memory Limit: 65536K Total Submissions: 11047 Accepted: 4725 Description In order to get from one of the F (1 <= F <= 5,000) grazing fields (which are numbered 1..F) to another field, Bessie and the rest of the…
[LeetCode]435. Non-overlapping Intervals 解题报告(Python) 作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 题目地址:https://leetcode.com/problems/non-overlapping-intervals/description/ 题目描述: Given a collection of intervals, find the minimum number of…