给你一个字符串 s 和一个 长度相同 的整数数组 indices . 请你重新排列字符串 s ,其中第 i 个字符需要移动到 indices[i] 指示的位置. 返回重新排列后的字符串. 示例 1: 输入:s = "codeleet", indices = [4,5,6,7,0,2,1,3] 输出:"leetcode" 解释:如图所示,"codeleet" 重新排列后变为 "leetcode" . 示例 2: 输入:s = &…

Leetcode(8)字符串转换整数 [题目表述]: 请你来实现一个 atoi 函数,使其能将字符串转换成整数. 首先,该函数会根据需要丢弃无用的开头空格字符,直到寻找到第一个非空格的字符为止. 当我们寻找到的第一个非空字符为正或者负号时,则将该符号与之后面尽可能多的连续数字组合起来,作为该整数的正负号:假如第一个非空字符是数字,则直接将其与之后连续的数字字符组合起来,形成整数. 该字符串除了有效的整数部分之后也可能会存在多余的字符,这些字符可以被忽略,它们对于函数不应该造成影响. 注意:假如该…

The string "PAYPALISHIRING" is written in a zigzag pattern on a given number of rows like this: (you may want to display this pattern in a fixed font for better legibility) P A H N A P L S I I G Y I R And then read line by line: "PAHNAPLSII…

本文梳理对LeetCode上有关字符串习题的知识点,并给出对应的刷题建议.本文建议刷题的总数为32题.具体知识点如下图: 1.回文问题 题号:5. 最长回文子串,难度中等 题号:214. 最短回文串,难度困难 题号:564. 寻找最近的回文数,难度困难 2.子串问题(类似子集) 题号:76. 最小覆盖子串,难度困难 题号:115. 不同的子序列,难度困难 题号:522. 最长特殊序列 II,难度中等 题号:1163. 按字典序排在最后的子串,难度困难 3.表达式求值问题 题号:12. 整数转罗马…

You have a total of n coins that you want to form in a staircase shape, where every k-th row must have exactly k coins. Given n, find the total number of full staircase rows that can be formed. n is a non-negative integer and fits within the range of…

Given an encoded string, return it's decoded string. The encoding rule is: k[encoded_string], where the encoded_string inside the square brackets is being repeated exactly k times. Note that k is guaranteed to be a positive integer. You may assume th…

Given two strings s and t, determine if they are isomorphic. Two strings are isomorphic if the characters in s can be replaced to get t. All occurrences of a character must be replaced with another character while preserving the order of characters.…

Given a string s1, we may represent it as a binary tree by partitioning it to two non-empty substrings recursively. Below is one possible representation of s1 = "great": great / \ gr eat / \ / \ g r e at / \ a t To scramble the string, we may ch…

题意:判断字符串是否是回文字符串 先将所有的字母和数字字符保留,并将大写字母转化成小写字母,然后将字符串倒置,比较前后两个字符串是否相同. 该题最好的解法可以模仿 Leetcode 345 Reverse Vowels of a String 字符串处理 class Solution { public: bool isPalindrome(string s) { ; ; i< s.size(); ++i){ if(isalpha(s[i]) || isdigit(s[i])) { if(isup…

A magical string S consists of only '1' and '2' and obeys the following rules: The string S is magical because concatenating the number of contiguous occurrences of characters '1' and '2' generates the string S itself. The first few elements of strin…

Given a string S, check if the letters can be rearranged so that two characters that are adjacent to each other are not the same. If possible, output any possible result.  If not possible, return the empty string. Example 1: Input: S = "aab" Out…

Given two strings s1 and s2, write a function to return true if s2 contains the permutation of s1. In other words, one of the first string's permutations is the substring of the second string. Example 1: Input:s1 = "ab" s2 = "eidbaooo"…

Given two strings A and B of lowercase letters, return true if and only if we can swap two letters in A so that the result equals B. Example 1: Input: A = "ab", B = "ba" Output: true Example 2: Input: A = "ab", B = "ab&q…

We are given two strings, A and B. A shift on A consists of taking string A and moving the leftmost character to the rightmost position. For example, if A = 'abcde', then it will be 'bcdea' after one shift on A. Return True if and only if A can becom…

题目链接:https://leetcode.com/problems/combinations/#/description    Problem:给两个正数分别为n和k,求出从1,2.......n这n个数字选择k个数字作为一个组合,求出所有的组合.   数学问题:排列组合问题,可以得到这样的组合个数为:C(n,k)     代码实现:递归程序实现. 从1开始遍历到n为止,中间使用tempList保存每一个组合,只有当这个tempList的长度等于k时,将这个tempList添加到ans中.  …

1.题目描述 A website domain like "discuss.leetcode.com" consists of various subdomains. At the top level, we have "com", at the next level, we have "leetcode.com", and at the lowest level, "discuss.leetcode.com". When w…

1.问题描述 Reverse Vowels of a String Write a function that takes a string as input and reverse only the vowels of a string. Example 1: Given s = "hello", return "holle". Example 2: Given s = "leetcode", return "leotcede&quo…

这是悦乐书的第344次更新,第368篇原创 01 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第209题(顺位题号是893). You are given an array A of strings. Two strings S and T are special-equivalent if after any number of moves, S == T. A move consists of choosing two indices i and j with i % 2…

公众号:爱写bug(ID:icodebugs) 给定一个字符串,你需要反转字符串中每个单词的字符顺序,同时仍保留空格和单词的初始顺序. Given a string, you need to reverse the order of characters in each word within a sentence while still preserving whitespace and initial word order. 示例 1: 输入: "Let's take LeetCode co…

Given two non-negative numbers num1 and num2 represented as string, return the sum of num1 and num2. Note: The length of both num1 and num2 is < 5100. Both num1 and num2 contains only digits 0-9. Both num1 and num2 does not contain any leading zero.…

Given two non-negative integers num1 and num2represented as strings, return the product of num1 and num2, also represented as a string. Example 1: Input: num1 = "2", num2 = "3" Output: "6" Example 2: Input: num1 = "123&q…

题目描述 实现获取下一个排列的函数,算法需要将给定数字序列重新排列成字典序中下一个更大的排列. 如果不存在下一个更大的排列,则将数字重新排列成最小的排列(即升序排列). 必须原地修改,只允许使用额外常数空间. 以下是一些例子,输入位于左侧列,其相应输出位于右侧列. 1,2,3 → 1,3,2 3,2,1 → 1,2,3 1,1,5 → 1,5,1 来源:力扣(LeetCode) 题解 输入的数组为nums[n-1],本题目的解题思路是,从j=n-2往前遍历,判断nums[j+1,n-1]中是否有…

这是小川的第413次更新,第446篇原创 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第264题(顺位题号是1175).返回1到n的排列数,以使质数处于质数索引(索引从1开始).(请记住,当且仅当整数大于1,并且不能将其写为两个均小于它的正整数的乘积,它才是质数.)由于答案可能很大,因此请以10^9 + 7为模返回答案. 例如: 输入:n = 5 输出:12 说明:[1,2,5,4,3]是有效的排列,但是[5,2,3,4,1]并不是,因为素数5在索引1处. 输入:n = 100…

这是小川的第389次更新,第419篇原创 01 看题和准备 今天介绍的是LeetCode算法题中Easy级别的第251题(顺位题号是1047).给定一个小写字母的字符串S,重复删除两个相邻且相等的字母. 我们在S上反复删除,直到我们再也无法删除. 在完成所有此类重复删除后返回最后一个字符串.保证答案是独一无二的. 例如: 输入:"abbaca" 输出:"ca" 说明:在"abbaca"中我们可以删除"bb",因为字母相邻且相等…

字符串中的第一个唯一字符 题目地址:https://leetcode-cn.com/problems/first-unique-character-in-a-string/ 给定一个字符串,找到它的第一个不重复的字符,并返回它的索引.如果不存在,则返回 -1. 示例: s = "leetcode" 返回 0 s = "loveleetcode" 返回 2 提示:你可以假定该字符串只包含小写字母. 解法一:双指针 双指针比较,每指定一个值都要全文扫描有无重复 publ…

题意:有一个模板串,给你\(T\)个字符串,选取最短的子串,使其重新排列后包含模板串,求最短的子串的长度 题解:遍历字符串,记录每个字符出现的最后位置,每记录一个后再遍历子串,找到子串需要的所有的字符的最后出现的最小位置,如果合法,更新答案即可. 代码: const string tp="puleyaknoi"; int t; string s; map<char,int> last; int res; int main() { ios::sync_with_stdio(f…

作者: 负雪明烛 id: fuxuemingzhu 公众号:每日算法题 本文关键词:LeetCode,力扣,算法,算法题,字符串,并查集,刷题群 目录 题目描述 解题思路 并查集 代码 刷题心得 欢迎加入组织 日期 题目地址:https://leetcode-cn.com/problems/similar-string-groups/ 题目描述 如果交换字符串 X 中的两个不同位置的字母,使得它和字符串 Y 相等,那么称 X 和 Y 两个字符串相似.如果这两个字符串本身是相等的,那它们也是相似的…

在一个「平衡字符串」中,'L' 和 'R' 字符的数量是相同的. 给出一个平衡字符串 s,请你将它分割成尽可能多的平衡字符串. 返回可以通过分割得到的平衡字符串的最大数量. 示例 1: 输入:s = "RLRRLLRLRL" 输出:4 解释:s 可以分割为 "RL", "RRLL", "RL", "RL", 每个子字符串中都包含相同数量的 'L' 和 'R'. 示例 2: 输入:s = "RLLL…

给你一个数组 nums ,数组中有 2n 个元素,按 [x1,x2,...,xn,y1,y2,...,yn] 的格式排列. 请你将数组按 [x1,y1,x2,y2,...,xn,yn] 格式重新排列,返回重排后的数组. 示例 1: 输入:nums = [2,5,1,3,4,7], n = 3 输出:[2,3,5,4,1,7] 解释:由于 x1=2, x2=5, x3=1, y1=3, y2=4, y3=7 ,所以答案为 [2,3,5,4,1,7] 示例 2: 输入:nums = [1,2,3,4…

Write a function that takes a string as input and returns the string reversed. Example: Given s = "hello", return "olleh". 这道题没什么难度,直接从两头往中间走,同时交换两边的字符即可,参见代码如下: 解法一: class Solution { public: string reverseString(string s) { , right =…