随笔分类 - 字符串处理——后缀自动机
摘要：题意：给定字符串S，然后M个字符串T。Q次询问，每次给出(L,R,l,r)，问S[l,r]在L到R这些T字符串中，在哪个串出现最多，以及次数。 思路：把所有串建立SAM，然后可以通过倍增走到[l,r]在SAM上的位置p，然后在这个位置p上求，求的过程就是一个线段树求区间最值。 现在的关键是得到线段树
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摘要：题意：给定字符串S； Q次询问，每次询问给出(L,R,T)，让你在S[L,R]里面找一个字典序最小的子串，其字典序比T大。 没有则输出-1； 思路：比T字典序大，而且要求字典最小，显然就是在T的尾巴加一个很小的字符，如果不存在，则依次删去尾巴，直到“存在”。 而“存在”是指，前缀lim+一个字符‘x
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摘要：题解见：http://ecustacm.cn/contest/11/announcements A #include<bits/stdc++.h> #define rep(i,a,b) for(int i=a;i<=b;i++) using namespace std; const int maxn
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摘要：有方程dp[i]=min(dp[i-1]+A,dp[j]+B)；如果s[j+1,i]在s[i,j]中出现，所以我们就是要知道每个子串在s出现的第一个位置，这个可以hash实现或者sam，或者kmp实现。 pos[i][j]表示s[i,j]对应的sam的位置，occ[]，表示第一次出现的位置。
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摘要：You are given n strings ti. Each string has cost ci. Let's define the function of string , where ps, i is the number of occurrences of s in ti, |s| is
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摘要：KMP，扩展KMP和Manacher就不写了，感觉没多大意思。 之前感觉后缀自动机简直可以解决一切，所以不怎么写后缀数组。 马拉车主要是通过对称中心解决问题，有的时候要通过回文串的边界解决问题，这个时候回文树就用到了，又好写，又强大。 之前整理过一篇后缀自动机的。感觉还要整理一下，顺便把回文树，后缀
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摘要：You are given a string ss. You should answer nn queries. The ii-th query consists of integer kiki and string mimi. The answer for this query is the mi
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摘要：The Little Elephant loves strings very much. He has an array a from n strings, consisting of lowercase English letters. Let's number the elements of t
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摘要：Police headquarter is monitoring signal on different frequency levels. They have got two suspiciously encoded strings s1 and s2 from two different fre
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摘要：问题： Amateur astronomers Tom and Bob try to find radio broadcasts of extraterrestrial civilizations in the air. Recently they received some strange sig
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摘要：Beside other services, ACM helps companies to clearly state their “corporate identity”, which includes company logo but also other signs, like tradema
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摘要：后缀家族已知成员 后缀树 后缀数组 后缀自动机 后缀仙人掌 后缀预言 后缀Splay ？ 后缀树是后缀数组和后缀自动机的祖先? 功能还是比较强大的，在回文串或者字典序方面还是有用处。 而且现在已经有了线性的建树方法。 （但其实我也没用过后缀树。）下面对比后缀自动机和后缀数组 单个字符串问题 不等号是
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摘要：Oimaster and sevenk love each other. 题意： 给定一些模板串，询问每个匹配串在多少个模板串里出现过。 思路： 后缀数组办法： 全部模板串连接在一起SA排序，SA数组附件的串里面去验证原串，还没写，我说不清楚，大概是后缀数组+RMQ处理。 后缀自动机办法： 1，广义
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摘要：You may have wondered why most extraterrestrial life forms resemble humans, differing by superficial traits such as height, colour, wrinkles, ears, ey
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摘要：问题： The little cat is majoring in physics in the capital of Byterland. A piece of sad news comes to him these days: his mother is getting ill. Being w
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摘要：Given a string, we need to find the total number of its distinct substrings. Input T- number of test cases. T<=20;Each test case consists of one strin
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摘要：A substring of a string T is defined as: T( i, k)= TiTi +1... Ti+k -1, 1≤ i≤ i+k-1≤| T|. Given two strings A, B and one integer K, we define S, a set
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摘要：Once upon a time there was a famous actress. As you may expect, she played mostly Antique Comedies most of all. All the people loved her. But she was
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摘要：Problem Description In middle school, teachers used to encourage us to pick up pretty sentences so that we could apply those sentences in our own arti
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摘要：Problem Description 035 now faced a tough problem,his english teacher gives him a string,which consists with n lower case letter,he must figure out ho
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