30. 串联所有单词的子串 给定一个字符串 s 和一些长度相同的单词 words.找出 s 中恰好可以由 words 中所有单词串联形成的子串的起始位置. 注意子串要与 words 中的单词完全匹配,中间不能有其他字符,但不需要考虑 words 中单词串联的顺序. 示例 1: 输入: s = "barfoothefoobarman", words = ["foo","bar"] 输出:[0,9] 解释: 从索引 0 和 9 开始的子串分别是 &q…

题目链接: https://leetcode-cn.com/problems/substring-with-concatenation-of-all-words/ 题目描述: 给定一个字符串 s 和一些长度相同的单词 words.找出 s 中恰好可以由 words 中所有单词串联形成的子串的起始位置. 注意子串要与 words 中的单词完全匹配,中间不能有其他字符,但不需要考虑 words 中单词串联的顺序. 示例: 示例 1: 输入: s = "barfoothefoobarman"…

见注释.滑动窗口还是好用. class Solution { public: vector<int> findSubstring(string s, vector<string>& words) { vector<int>res; if(words.empty()||s.empty()) return res; map<string,int>allWords; int wordLen=words[0].size(); int wordNum=word…

You are given a string, s, and a list of words, words, that are all of the same length. Find all starting indices of substring(s) in s that is a concatenation of each word in words exactly once and without any intervening characters. Example 1: Input…

You are given a string, s, and a list of words, words, that are all of the same length. Find all starting indices of substring(s) in s that is a concatenation of each word in words exactly once and without any intervening characters. For example, giv…

[030-Substring with Concatenation of All Words(串联全部单词的子串)] [LeetCode-面试算法经典-Java实现][全部题目文件夹索引] 原题 You are given a string, s, and a list of words, words, that are all of the same length. Find all starting indices of substring(s) in s that is a concate…

30. 与所有单词相关联的字串 这个题做了大概两个小时左右把...严重怀疑leetcode的judge机器有问题.同样的代码交出来不同的运行时长,能不能A题还得看运气? 大致思路是,给words生成一关于s的字典,用来记录每个word在s中出现的所有位置,注意可能会出现相同的word.然后递归枚举words的排列情况,一一校验是否符合条件(即连在一起).用到了递归+记忆化搜索+kmp+几个剪枝 一直最后几个测试用例上TLE,囧啊,甚至一度怀疑是不是还有更优的做法. 然后开始考虑剪枝: 记忆化搜索…

与所有单词相关联的字串 给定一个字符串 s 和一些长度相同的单词 words.在 s 中找出可以恰好串联 words 中所有单词的子串的起始位置. 注意子串要与 words 中的单词完全匹配,中间不能有其他字符,但不需要考虑 words 中单词串联的顺序. 示例 1: 输入: s = "barfoothefoobarman", words = ["foo","bar"] 输出: [0,9] 解释: 从索引 0 和 9 开始的子串分别是 "…

@author: ZZQ @software: PyCharm @file: leetcode30_findSubstring.py @time: 2018/11/20 19:14 题目要求: 给定一个字符串 s 和一些长度相同的单词 words.在 s 中找出可以恰好串联 words 中所有单词的子串的起始位置. 注意子串要与 words 中的单词完全匹配,中间不能有其他字符,但不需要考虑 words 中单词串联的顺序. 示例 1: 输入: s = "barfoothefoobarman&qu…

题目链接 [题解] 开个字典树记录下所有的单词. 然后注意题目的已知条件 每个单词的长度都是一样的. 这就说明不会出现某个字符串是另外一个字符串的前缀的情况(除非相同). 所以可以贪心地匹配(遇到什么字符就在字典树里面沿着边从根往下走就好). 假设给的单词的个数为len.(每个单词的长度都是L) 显然从每个位置开始都要匹配len次.而且每次都要匹配L个字符. 然后因为可能会出现一个单词出现多次的情况. 那么你得记录一下之前某个单词用了多少次. [代码] class Solution { publ…

58. 最后一个单词的长度 给定一个仅包含大小写字母和空格 ' ' 的字符串 s,返回其最后一个单词的长度. 如果字符串从左向右滚动显示,那么最后一个单词就是最后出现的单词. 如果不存在最后一个单词,请返回 0 . 说明:一个单词是指仅由字母组成.不包含任何空格的 最大子字符串. 示例: 输入: "Hello World" 输出: 5 class Solution { public int lengthOfLastWord(String s) { int count=0; for(in…

先对words中的单词排列组合,然后对s滑窗操作:部分样例超时,代码如下: class Solution { public: vector<int> findSubstring(string s, vector<string>& words) { //dfs找出words所有组合,然后在s滑窗 //排除异常情况 int len=0; for(auto w:words){ len+=w.size(); } if(len==0 || s.size()==0 || len>…

5. 最长回文子串 给定一个字符串 s,找到 s 中最长的回文子串.你可以假设 s 的最大长度为 1000. 示例 1: 输入: "babad" 输出: "bab" 注意: "aba" 也是一个有效答案. 示例 2: 输入: "cbbd" 输出: "bb" 来源:力扣(LeetCode) 链接:https://leetcode-cn.com/problems/longest-palindromic-subs…

题目描述: 给定一个字符串 s 和一些长度相同的单词 words.在 s 中找出可以恰好串联 words 中所有单词的子串的起始位置. 注意子串要与 words 中的单词完全匹配,中间不能有其他字符,但不需要考虑 words 中单词串联的顺序. 示例 1: 输入: s = "barfoothefoobarman", words = ["foo","bar"] 输出: [0,9] 解释: 从索引 0 和 9 开始的子串分别是 "barfo…

Given a 2D board and a list of words from the dictionary, find all words in the board. Each word must be constructed from letters of sequentially adjacent cell, where "adjacent" cells are those horizontally or vertically neighboring. The same le…

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 only letters a-z or .. A . means it can represent any one letter.…

Find all possible combinations of k numbers that add up to a number n, given that only numbers from 1 to 9 can be used and each combination should be a unique set of numbers. Ensure that numbers within the set are sorted in ascending order. Example 1…

Given a string S, you are allowed to convert it to a palindrome by adding characters in front of it. Find and return the shortest palindrome you can find by performing this transformation. For example: Given "aacecaaa", return "aaacecaaa&qu…

There are a total of n courses you have to take, labeled from 0 to n - 1. Some courses may have prerequisites, for example to take course 0 you have to first take course 1, which is expressed as a pair: [0,1] Given the total number of courses and a l…

Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded by…

Say you have an array for which the ith element is the price of a given stock on day i. Design an algorithm to find the maximum profit. You may complete at most k transactions. 解题思路: https://leetcode.com/discuss/18330/is-it-best-solution-with-o-n-o-1…

Suppose a sorted array is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2). Find the minimum element. The array may contain duplicates. 解题思路: 参考Java for LeetCode 081 Search in Rotated Sorted Array II J…

Suppose a sorted array is rotated at some pivot unknown to you beforehand. (i.e., 0 1 2 4 5 6 7 might become 4 5 6 7 0 1 2). Find the minimum element. You may assume no duplicate exists in the array. 解题思路: 本题和Java for LeetCode 033 Search in Rotated S…

The set [1,2,3,…,n] contains a total of n! unique permutations. By listing and labeling all of the permutations in order, We get the following sequence (ie, for n = 3): "123" "132" "213" "231" "312" "…

Given an integer n, generate a square matrix filled with elements from 1 to n2 in spiral order. For example, Given n = 3, You should return the following matrix: [ [ 1, 2, 3 ], [ 8, 9, 4 ], [ 7, 6, 5 ]] 解题思路: 参考Java for LeetCode 054 Spiral Matrix,修改下…

Given a set of non-overlapping intervals, insert a new interval into the intervals (merge if necessary). You may assume that the intervals were initially sorted according to their start times. Example 1: Given intervals [1,3],[6,9], insert and merge…

Given an array of non-negative integers, you are initially positioned at the first index of the array. Each element in the array represents your maximum jump length at that position. Determine if you are able to reach the last index. For example: A =…

Given a collection of numbers that might contain duplicates, return all possible unique permutations. For example, [1,1,2] have the following unique permutations: [1,1,2], [1,2,1], and [2,1,1]. 解题思路一: 发现Java for LeetCode 046 Permutations自己想多了,代码直接拿来用…

Implement wildcard pattern matching with support for '?' and '*'. '?' Matches any single character. '*' Matches any sequence of characters (including the empty sequence). The matching should cover the entire input string (not partial). The function p…

Given a string containing just the characters '(' and ')', find the length of the longest valid (well-formed) parentheses substring. For "(()", the longest valid parentheses substring is "()", which has length = 2. Another example is &…