原文链接:http://laphets1.gotoip3.com/?id=18 Description 给出一个由小写字母组成的字符串,其中一些字母被染黑了,用?表示.已知原来的串不是 一个回文串,现在让你求出字典序最小的可能的串.像’a’,’aba’,’abba’这样对称的串叫做回 文串. 每个测试点有5 组小测试点. Input 5 行,5 个字符串. Output 5 行,5 个字符串.若无解,输出”Orz,I can not find it!” 这个题目主要就是利用了一种贪心的思想  总…

假设没有操作1,就是裸的回文串自己主动机...... 能够从头部插入字符的回文串自己主动机,维护两个last点就好了..... 当整个串都是回文串的时候把两个last统一一下 Victor and String Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 524288/262144 K (Java/Others) Total Submission(s): 30    Accepted Submission(s): 9 Probl…

两道差不多的题,都是回文自动机right集合处理相关. Victor and String Victor loves to play with string. He thinks a string is charming as the string is a palindromic string. Victor wants to play n times. Each time he will do one of following four operations. add a char c to…

题意: 记录不相交的回文串对数 题解: 正着反着都来一遍回文树 用sum1[i] 表示到 i 位置,出现的回文串个数的前缀和 sun2[i]表示反着的个数 ans+=sum1[i-1]*sum2[i] #include <set> #include <map> #include <stack> #include <queue> #include <cmath> #include <ctime> #include <cstdio&…

O(n)的复杂度求回文串:Manacher算法 定义一个回文值,字符串S是K重回文串,当且仅当S是回文串,且其长度为⌊N/2⌋的前缀和长度为⌊N/2⌋的后缀是K−1重回文串 现在给一个2*10^6长度的字符串,求其每个前缀的最大回文值之和. 设dp[i]为长度为i的前缀的最大回文值. 当长度为i的前缀的字符串是回文串的时候,有:dp[i]=dp[i/2]+1 若不是回文串 dp[i]=0 接下来就是怎么样快速的判断回文串了,推荐算法Manacher算法. Manacher算法先对字符串进行修改…

Sample Input aca aaaa Sample Output 3 15 题意: 多组输入,每次给定字符串S(|S|<1e5),求多少对不相交的回文串. 思路:可以用回文树求出以每个位置结尾的回文串数,那么累加得到前缀和: 倒着再做一遍得到每个位置为开头的回文串数,乘正向求出的前缀和即可. #include<bits/stdc++.h> #define ll long long #define rep(i,a,b) for(int i=a;i<=b;i++) #define…

Given a string which consists of lowercase or uppercase letters, find the length of the longest palindromes that can be built with those letters. This is case sensitive, for example "Aa" is not considered a palindrome here. Note: Assume the leng…

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…

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 partitioning ["aa"…

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","a","…