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…

Shortest Palindrome 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", retur…

题目如下: You are given a string s containing lowercase letters and an integer k. You need to : First, change some characters of s to other lowercase English letters. Then divide s into k non-empty disjoint substrings such that each substring is palindro…

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 HashTable 相似题目 参考资料 日期 题目地址:https://leetcode.com/problems/palindrome-pairs/description/ 题目描述 Given a list of unique words, find all pairs of distinct indices (i, j) in the give…

作者: 负雪明烛 id: fuxuemingzhu 个人博客: http://fuxuemingzhu.cn/ 公众号:负雪明烛 本文关键词:回文数,回文,题解,Leetcode, 力扣,Python, C++, Java 目录 题目描述 题目大意 解题方法 判断回文字符串 翻转数字 日期 题目地址:https://leetcode.com/problems/palindrome-number/#/description 题目描述 Determine whether an integer is…

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 日期 题目地址:https://leetcode.com/problems/palindrome-linked-list/#/description 题目描述 Given a singly linked list, determine if it is a palindrome. Follow up: Could you do it in O(n)…

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 日期 题目地址:https://leetcode.com/problems/palindrome-partitioning/description/ 题目描述 Given a string s, partition s such that every substring of the partition is a palindrome. Re…

题目简述: Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example, "A man, a plan, a canal: Panama" is a palindrome. "race a car" is not a palindrome. Note: Have you conside…

Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. For example,"A man, a plan, a canal: Panama" is a palindrome."race a car" is not a palindrome. Note:Have you consider that th…

题目描述: Determine whether an integer is a palindrome. Do this without extra space. 解题分析: ^_^个人觉得这道题没有什么可分析的,直接看代码就能明白^_^. 具体代码: public class Solution { public static boolean isPalindrome(int x) { if(x<0) return false; if(x>=0&x<=9) return true;…

[ 问题: ] Given a string, determine if it is a palindrome, considering only alphanumeric characters and ignoring cases. 直译:给你一个字符串, 判定它是否是回文(仅仅统计字母.数字.其它字符请忽略). For example, "A man, a plan, a canal: Panama" is a palindrome. "race a car"…

234. Palindrome Linked List 1. 使用快慢指针找中点的原理是fast和slow两个指针,每次快指针走两步,慢指针走一步,等快指针走完时,慢指针的位置就是中点.如果是偶数个数,正好是一半一半,如果是奇数个数,慢指针正好在中间位置,判断回文的时候不需要比较该位置数据. 注意好好理解快慢指针的算法原理及应用. 2. 每次慢指针走一步,都把值存入栈中,等到达中点时,链表的前半段都存入栈中了,由于栈的后进先出的性质,就可以和后半段链表按照回文对应的顺序比较. solution…

Palindrome Linked List Given a singly linked list, determine if it is a palindrome. Follow up:Could you do it in O(n) time and O(1) space? 解法一: 一次遍历,装入vector,然后再一次遍历判断回文. 时间复杂度O(n),空间复杂度O(n) /** * Definition for singly-linked list. * struct ListNode…

@requires_authorization @author johnsondu @create_time 2015.7.13 9:48 @url [palindrome-number](https://leetcode.com/problems/palindrome-number/) /************************ * 分离出最左边和最右边的数 * 然后依次对照就可以 ***********************/ class Solution { public: bo…

Palindrome Number Determine whether an integer is a palindrome. Do this without extra space. click to show spoilers. Some hints: Could negative integers be palindromes? (ie, -1) If you are thinking of converting the integer to string, note the restri…

Palindrome Partitioning II  Given a string s, partition s such that every substring of the partition is a palindrome. Return the minimum cuts needed for a palindrome partitioning of s. For example, given s = "aab",Return 1 since the palindrome p…

Palindrome Partitioning Given a string s, partition s such that every substring of the partition is a palindrome. Return all possible palindrome partitioning of s. For example, given s = "aab",Return [ ["aa","b"], ["a&qu…

Determine whether an integer is a palindrome. Do this without extra space. Some hints: Could negative integers be palindromes? (ie, -1) If you are thinking of converting the integer to string, note the restriction of using extra space. You could also…

题目: Determine whether an integer is a palindrome. Do this without extra space. Some hints: Could negative integers be palindromes? (ie, -1) If you are thinking of converting the integer to string, note the restriction of using extra space. You could…

原题 Given a string, determine if a permutation of the string could form a palindrome. For example, "code" -> False, "aab" -> True, "carerac" -> True. 解析 判断是否可以组成回文 给一个字符串,判断字符串中的字符是否可以组成回文 思路 其实思路都一样,计算字符串中的字符个数:若字符串的…

很久没有做题了,今天写个简单难度的练练手感. Given a non-empty string s, you may delete at most one character. Judge whether you can make it a palindrome. Example 1: Input: "aba" Output: True Example 2: Input: "abca" Output: True Explanation: You could dele…

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 字典 日期 题目地址:https://leetcode-cn.com/problems/palindrome-permutation/ 题目描述 Given a string, determine if a permutation of the string could form a palindrome. Example 1: Input: "cod…

题目如下: 解题思路:对于任意一个word,要找出在wordlist中是否存在与之能组成回文的其他words,有两种思路.一是遍历wordlist:二是对word本身进行分析,找出能组成回文的words,并判断是否存在于wordlist中.显然,第二种思路比较的次数要少很多.怎么找出能组成回文的words呢?只要把后面的字符依次往前复制,并判断是否为回文,直到全部字符复制完成为止,这就能得到所有能与之组成回文的words.以abcd作为前缀为例,首先把d复制到abcd前面得到dabcd,接下来依…

[3]Longest Substring Without Repeating Characters (2019年1月22日,复习) [5]Longest Palindromic Substring (2019年1月22日,复习) [6]ZigZag Conversion (2019年1月22日,复习) [8]String to Integer (atoi) (2019年1月22日,复习) [10]Regular Expression Matching (2019年1月22日,复习) [12]In…

题目等级:Easy 题目描述: Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward. Example 1: Input: 121 Output: true Example 2: Input: -121 Output: false Explanation: From left to right, it reads -12…

[1]Two Sum (2018年11月9日,k-sum专题,算法群衍生题) 给了一个数组 nums, 和一个 target 数字,要求返回一个下标的 pair, 使得这两个元素相加等于 target . 题解:我这次最大范围的优化代码, hash-table + one pass,时间复杂度 O(N),空间复杂度 O(N).重点在于动态找,一边生成hash-table的同时去找答案,不是先生成hash-table再开始找答案. //这种类似 hash 的能用 unordered_map 就不要…

[LeetCode]Minimum Depth of Binary Tree Given a binary tree, find its minimum depth. The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node. 递归和非递归,此提比较简单.广度优先遍历即可.关键之处就在于如何保持访问深度. 下面是4种代码: im…

链接:https://leetcode.com/tag/heap/ [23] Merge k Sorted Lists [215] Kth Largest Element in an Array (无序数组中最小/大的K个数)(2018年11月30日第一次复习) 给了一个无序数组,可能有重复数字,找到第 k 个最大的元素并且返回这个元素值. 题解:直接用直接用个堆保存数组中最大的 K 个数.时间复杂度是 O(NlogK). //时间复杂度是 O(NlogK), 用堆辅助. class Solut…

[600] Non-negative Integers without Consecutive Ones [629] K Inverse Pairs Array [638] Shopping Offers [639] Decode Ways II [646] Maximum Length of Pair Chain [647] Palindromic Substrings 给定一个字符串,判断有多少子串是 palindromic 的,子串就算所有字母都相同,但是开始和结束位置的下标不同,也算不同…

[2]Add Two Numbers (2018年12月23日,review) 链表的高精度加法. 题解:链表专题:https://www.cnblogs.com/zhangwanying/p/9797184.html [7]Reverse Integer (2018年12月23日, review) 给了一个32位的整数,返回它的reverse后的整数.如果reverse后的数超过了整数的范围,就返回 0. Example 1: Input: 123 Output: 321 Example 2:…