题目链接:点击打开链接 #include<stdio.h> #include<iostream> #include<string.h> #include<set> #include<vector> #include<map> #include<math.h> #include<queue> #include<string> #include<stdlib.h> #include<a…

最近接触了一点字符串算法,其实也就是一个简单的最大回文串算法,给定字符串s,求出最大字符串长度. 算法是这样的, 用'#'将s字符串中的每个字符分隔,比如s = "aba",分割后变成#a#b#a#,然后利用下面的算法: pre: mx ←0    for i: = 1 to n-1         if(mx>i)           p[i] = min(p[2*id-i], mx-i)         else p[i] = 1        while(str[i+p[i…

题目链接:http://codeforces.com/contest/7/problem/D D. Palindrome Degree time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output String s of length n is called k-palindrome, if it is a palindrome itself…

题目链接:https://codeforces.com/problemset/problem/1056/E One of Arkady's friends works at a huge radio telescope. A few decades ago the telescope has sent a signal $s$ towards a faraway galaxy. Recently they've received a response $t$ which they believe…

个人心得:这题就是要确定是否为回文串,朴素算法会超时,所以想到用哈希,哈希从左到右和从右到左的key值一样就一定是回文串, 那么问题来了,正向还能保证一遍遍历,逆向呢,卡住我了,后面发现网上大神的秦九韶算法用上了,厉害了. 关于哈希,这题用的是最简单的哈希思想,就是用M取合理的素数,这题取得是3, 然后正向就是 a+=a*M+ch[i].逆向用秦九韶可以在循环的时候算出来, 举个例子比如三个值1,2,3. 假如逆向开始 则 (((0+s[3])*M+s[2])*M+s[1]);化简就等于s[1]…

题目:http://blog.csdn.net/winddreams/article/details/44218961 求出每一个点为中心的最长字符串,推断该串是不是从开头的回文串. #include <cstdio> #include <cstring> #include <algorithm> using namespace std ; int p[12000000] , dp[6000000]; char s[12000000] , str[12000000] ;…

D. Palindrome Degree 题目连接: http://www.codeforces.com/contest/7/problem/D Description String s of length n is called k-palindrome, if it is a palindrome itself, and its prefix and suffix of length are (k - 1)-palindromes. By definition, any string (ev…

Andy the smart computer science student was attending an algorithms class when the professor asked the students a simple question, "Can you propose an efficient algorithm to find the length of the largest palindrome in a string?" A string is sai…

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]:http://codeforces.com/contest/514/problem/C [题意] 给你n个字符串; 然后给你m个询问;->m个字符串 对于每一个询问字符串 你需要在n个字符串里面找到和它的长度相同,且只有一个位置的字符不同的字符串; 或者告知这是不存在的; [题解] 字符串hash 因为只有3个字符 所以权值就为3^x; 找个大质数取模就好: 不够大就再大一点.. 然后对于每一位,尝试换成其他两个字母,看看存不存在; [Number Of WA] 3 [完整代码]…