题意 给n对括号, 求所有的合法括号序列 解法 递归 递归过程中, 值传递来实现回溯 代码 vector<string> ans; void genParenthesis(string p, int L, int R) { if (L < 0 || R < 0) return; if (L == 0 && R == 0) { ans.push_back(p); return; }
2116. Check if a Parentheses String Can Be Valid Medium 54219Add to ListShare A parentheses string is a non-empty string consisting only of '(' and ')'. It is valid if any of the following conditions is true: It is (). It can be wr
原题链接在这里：https://leetcode.com/problems/minimum-insertions-to-balance-a-parentheses-string/ 题目： Given a parentheses string s containing only the characters '(' and ')'. A parentheses string is balanced if: Any left parenthesis '(&#
［抄题］： You need to construct a binary tree from a string consisting of parenthesis and integers. The whole input represents a binary tree. It contains an integer followed by zero, one or two pairs of parenthesis. The integer represents the root's valu
Given a string s containing only three types of characters: '(', ')' and '*', return true if s is valid. The following rules define a valid string: Any left parenthesis '(' must have a corresponding right parenthes
Description Given a string containing only three types of characters: ‘(’, ‘)’ and ‘*’, write a function to check whether this string is valid. We define the validity of a string by these rules: Any left parenthesis ‘(’ must have a corresponding
Bobo has a balanced parenthesis sequence P=p 1 p 2…p n of length n and q questions. The i-th question is whether P remains balanced after p ai and p bi swapped. Note that questions are individual so that they have no affect on others. Parenthesis s
