能匹配上子串的节点对它的所有parent都有贡献 在树上转移即可 #include<cstdio> #include<algorithm> #include<cstring> #include<iostream> #include<queue> #define ll long long #define M 200010 using namespace std; int read() { int nm = 0, f = 1; char c = ge…

[SP1812]LCS2 - Longest Common Substring II 题面 洛谷 题解 你首先得会做这题. 然后就其实就很简单了, 你在每一个状态\(i\)打一个标记\(f[i]\)表示状态\(i\)能匹配到最长的子串长度, 显然\(f[i]\)可以上传给\(f[i.fa]\). 然后去每个串和第\(1\)个串\(f\)的最小值的最大值即可. 代码 #include <iostream> #include <cstdio> #include <cstdlib&…

LCS2 - Longest Common Substring II A string is finite sequence of characters over a non-empty finite set Σ. In this problem, Σ is the set of lowercase letters. Substring, also called factor, is a consecutive sequence of characters occurrences at leas…

地址:http://www.spoj.com/problems/LCS2/ 题面: LCS2 - Longest Common Substring II no tags  A string is finite sequence of characters over a non-empty finite set Σ. In this problem, Σ is the set of lowercase letters. Substring, also called factor, is a con…

LCS2 - Longest Common Substring II no tags  A string is finite sequence of characters over a non-empty finite set Σ. In this problem, Σ is the set of lowercase letters. Substring, also called factor, is a consecutive sequence of characters occurrence…

spoj 1812 LCS2 - Longest Common Substring II 题意: 给出最多n个字符串A[1], ..., A[n], 求这n个字符串的最长公共子串. 限制: 1 <= n <= 10 |A[i]| <= 1e5 思路: 和spoj 1811 LCS几乎相同的做法 把当中一个A建后缀自己主动机 考虑一个状态s, 假设A之外的其它串对它的匹配长度各自是a[1], a[2], ..., a[n - 1], 那么min(a[1], a[2], ..., a[n -…

LCS2 - Longest Common Substring II 多个字符串找最长公共子串 以其中一个串建\(SAM\),然后用其他串一个个去匹配,每次的匹配方式和两个串找\(LCS\)一样,就是要记录\(SAM\)的每个状态和当前匹配串匹配的最大值\(maxx\),这个在匹配完一个串之后需要通过\(parent\)树上传最大匹配值,同时要更新一个最小值\(minn\),来表示每个节点和当前已经匹配过的所有串能匹配上的最大值,这个需要每次匹配一个串之后和当前节点的\(maxx\)取\(min…

对于本题这样的多字符串的子串匹配问题,其实用广义后缀自动机就可以很好的解决,感觉会比普通的后缀自动机做法方便一些. 首先记录出每个节点被多少个字符串更新,也就是记录每个节点有多少个字符串能到达它,可以通过在\(Parent\)树上求子树和处理出. 若所有字符串都能到达一个节点,也就是该节点所对应的串为所有字符串的子串,那么该节点是一个合法的转移状态. 那么就可以直接拿这些字符串中的任意一个字符串在自动机上匹配,就像LCS - Longest Common Substring一样,只向合法状态转移…

A string is finite sequence of characters over a non-empty finite set \(\sum\). In this problem, \(\sum\) is the set of lowercase letters. Substring, also called factor, is a consecutive sequence of characters occurrences at least once in a string. N…

A string is finite sequence of characters over a non-empty finite set Σ. In this problem, Σ is the set of lowercase letters. Substring, also called factor, is a consecutive sequence of characters occurrences at least once in a string. Now your task i…