马拉车用于解决最长回文子串问题,重点是子串,而不是子序列,时间复杂度为O(n). 解释一下变量的意义: Len[i]数组去存第i个位置到mx位置的长度 id记录上一次操作的位置(这个操作可以看模板) mx标记上一次的最长子串的最右端 模板: 1 void init() //这个是用来处理字符串的 2 { 3 memset(str,0,sizeof(str)); 4 int k=0; 5 str[k++]='$'; 6 for(int i=0;i<len;++i) 7 str[k++]='#',s…

https://nanti.jisuanke.com/t/15428 题目大意:离散表示的字符串,求其最长回文串长度. 解题关键:若只用Manacher算法,在统计sum时会超时,所以加一个树状数组来维护前n项和,即可AC. 注意进行Manacher时,i是从1开始的,不要小也不要大. n天后更新:以前一直没搞清离线与动态维护的区别,今天终于理解了,此题可以开始直接离线求前n项和,因为以后不再改变,所以此题不需要bit维护.直接用一个数组统计一下前n项和即可. #include<bits/std…

[学习笔记]字符串-马拉车(Manacher) 一:[前言] 马拉车用于求解连续回文子串问题,效率极高. 其核心思想与 \(kmp\) 类似:继承. --引自 \(yyx\) 学姐 二:[算法原理] 对于任意一个回文串 \(a\),设其中点为 \(mid\)(为方便描述,偶数串则在正中央加一个位置),那么根据定义,有: \(a[mid-1]==a[mid+1]\) \(a[mid-2]==a[mid+2]\) \(...\) 可知: 如果 \(a[mid-x]\) 可以形成半径为 \(r\) 的…

E. Palindrome QueryTime Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100570/problem/E Description De Prezer loves palindrome strings. A string s1s2...sn is palindrome if and only if it is equal to its reverse. De Prezer also love…

http://poj.org/problem?id=3974 Palindrome Time Limit: 15000MSMemory Limit: 65536K Total Submissions: 2707Accepted: 995 Description Andy the smart computer science student was attending an algorithms class when the professor asked the students a simpl…

Palindrome Time Limit: 15000MS   Memory Limit: 65536K Total Submissions: 6183   Accepted: 2270 Description Andy the smart computer science student was attending an algorithms class when the professor asked the students a simple question, "Can you pro…

 Palindrome Time Limit:15000MS     Memory Limit:65536KB     64bit IO Format:%I64d & %I64u Submit Status Description Andy the smart computer science student was attending an algorithms class when the professor asked the students a simple question, &quo…

题目链接: http://codeforces.com/problemset/problem/7/D D. Palindrome Degree time limit per test1 secondmemory limit per test256 megabytes 问题描述 String s of length n is called k-palindrome, if it is a palindrome itself, and its prefix and suffix of length…

题目链接: Palindrome Time Limit: 6000/3000 MS (Java/Others)    Memory Limit: 262144/262144 K (Java/Others)Total Submission(s): 113    Accepted Submission(s): 44 Problem Description Alice like strings, especially long strings. For each string, she has a s…

Palindrome Time Limit: 15000MS   Memory Limit: 65536K Total Submissions: 14021   Accepted: 5374 题目链接:http://poj.org/problem?id=3974 Description: Andy the smart computer science student was attending an algorithms class when the professor asked the st…