Examples: Input: S = "a1b2" Output: ["a1b2", "a1B2", "A1b2", "A1B2"] Input: S = "3z4" Output: ["3z4", "3Z4"] Input: S = "12345" Output: ["12345"] class Sol…

problem 784. Letter Case Permutation 参考 1. Leetcode_easy_784. Letter Case Permutation; 2. Grandyang; 完…

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 回溯法 循环 日期 题目地址:https://leetcode.com/problems/letter-case-permutation/description/ 题目描述 Given a string S, we can transform every letter individually to be lowercase or uppercase…

［抄题］: Given a string S, we can transform every letter individually to be lowercase or uppercase to create another string.  Return a list of all possible strings we could create. Examples: Input: S = "a1b2" Output: ["a1b2", "a1B2&q…

Given a string S, we can transform every letter individually to be lowercase or uppercase to create another string.  Return a list of all possible strings we could create. Examples: Input: S = "a1b2" Output: ["a1b2", "a1B2",…

题目要求 Given a string S, we can transform every letter individually to be lowercase or uppercase to create another string.  Return a list of all possible strings we could create. 题目分析及思路 给定一个字符串,考虑每个字母都有大小写,返回可能的所有字符串.由于每个字母都有两种形式,可结合二进制的思想,有n个字母就有2^n种…

Given a string S, we can transform every letter individually to be lowercase or uppercase to create another string.  Return a list of all possible strings we could create. Examples: Input: S = "a1b2" Output: ["a1b2", "a1B2",…

网址:https://leetcode.com/problems/letter-case-permutation/ basic backtracking class Solution { public: void backTrack(string s, string res, int i, vector<string> &ans) { if (i == s.size()) { ans.push_back(res); return; } if (!isalpha(s[i])) backT…

这个题的思想很重要,两种方法 第一种,回溯法 class Solution { public: int sz; vector<string> letterCasePermutation(string S) { vector<string> res; sz=S.size(); backtrack(S,,res); return res; } void backtrack(string &s,int i,vector<string> &res) { if(i…

作者: 负雪明烛 id: fuxuemingzhu 个人博客:http://fuxuemingzhu.cn/ 个人公众号:负雪明烛 本文关键词:电话号码, 字母组合,回溯法,题解,leetcode, 力扣,Python, C++, Java 目录 题目描述 题目大意 解题方法 回溯法 内置函数 循环 日期 题目地址:https://leetcode.com/problems/generate-parentheses/description/ 题目描述 Given a string contain…

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