【Codeforces666E】Forensic Examination 后缀自动机 + 线段树合并
E. Forensic Examination
The country of Reberland is the archenemy of Berland. Recently the authorities of Berland arrested a Reberlandian spy who tried to bring the leaflets intended for agitational propaganda to Berland illegally . The most leaflets contain substrings of the Absolutely Inadmissible Swearword and maybe even the whole word.
Berland legal system uses the difficult algorithm in order to determine the guilt of the spy. The main part of this algorithm is the following procedure.
All the m leaflets that are brought by the spy are numbered from 1 to m. After that it's needed to get the answer to q queries of the following kind: "In which leaflet in the segment of numbers [l, r] the substring of the Absolutely Inadmissible Swearword [pl, pr] occurs more often?".
The expert wants you to automate that procedure because this time texts of leaflets are too long. Help him!
The first line contains the string s (1 ≤ |s| ≤ 5·105) — the Absolutely Inadmissible Swearword. The string s consists of only lowercase English letters.
The second line contains the only integer m (1 ≤ m ≤ 5·104) — the number of texts of leaflets for expertise.
Each of the next m lines contains the only string ti — the text of the i-th leaflet. The sum of lengths of all leaflet texts doesn't exceed 5·104. The text of the leaflets consists of only lowercase English letters.
The next line contains integer q (1 ≤ q ≤ 5·105) — the number of queries for expertise.
Finally, each of the last q lines contains four integers l, r, pl, pr (1 ≤ l ≤ r ≤ m, 1 ≤ pl ≤ pr ≤ |s|), where |s| is the length of the Absolutely Inadmissible Swearword.
Print q lines. The i-th of them should contain two integers — the number of the text with the most occurences and the number of occurences of the substring [pl, pr] of the string s. If there are several text numbers print the smallest one.
suffixtree
3
suffixtreesareawesome
cartesiantreeisworsethansegmenttree
nyeeheeheee
2
1 2 1 10
1 3 9 10
1 1
3 4
Solution
题目大意:给出一个模板串S和M个特殊串,每次询问S的[l,r]这个子串出现在编号为[pl,pr]的特殊串中最多出现次数以及其编号。
显然可以把所有串连起来建后缀自动机。
对于每个特殊串的节点,可以认为它包含一种颜色,然后查询操作实际上就是查询一个子树颜色数。
这个可以从叶子节点利用线段树合并得到;
总的复杂度是$O(NlogN)$
Code
#include<iostream>
#include<cstdio>
#include<cmath>
#include<algorithm>
#include<cstring>
using namespace std;
inline int read()
{
int x=0,f=1; char ch=getchar();
while (ch<'0' || ch>'9') {if (ch=='-') f=-1; ch=getchar();}
while (ch>='0' && ch<='9') {x=x*10+ch-'0'; ch=getchar();}
return x*f;
} #define MAXN 500010
#define MAXS 1230010 int N,M,Q,pos[MAXN]; char S[MAXN],s[MAXN]; int root=1,sz=1,last=1,par[MAXS],son[MAXS][27],len[MAXS],st[MAXS],id[MAXS];
inline void Extend(int c)
{
int cur=++sz,p=last;
len[cur]=len[p]+1;
while (p && !son[p][c]) son[p][c]=cur,p=par[p];
if (!p) par[cur]=root;
else {
int q=son[p][c];
if (len[p]+1==len[q]) par[cur]=q;
else {
int nq=++sz;
memcpy(son[nq],son[q],sizeof(son[nq]));
len[nq]=len[p]+1; par[nq]=par[q];
while (p && son[p][c]==q) son[p][c]=nq,p=par[p];
par[q]=par[cur]=nq;
}
}
last=cur;
} inline void Sort()
{
for (int i=0; i<=sz; i++) st[i]=0;
for (int i=1; i<=sz; i++) st[len[i]]++;
for (int i=0; i<=sz; i++) st[i]+=st[i-1];
for (int i=1; i<=sz; i++) id[st[len[i]]--]=i;
} #define Pa pair<int,int>
#define MP make_pair
#define Max first
#define Id second struct SgtNode{
Pa key;
int lson,rson;
}tree[MAXS*23]; inline Pa operator * (const Pa & A,const Pa &B) {return A.Max==B.Max? (A.Id<B.Id? A:B):(A.Max>B.Max? A:B);} inline Pa operator + (const Pa & A,const Pa &B) {return MP(A.Max+B.Max,A.Id);} int cnt,roots[MAXS],father[21][MAXS];
inline void Insert(int &x,int val,int l,int r)
{
if(!x) x=++cnt;
if (l==r) {tree[x].key.Max++,tree[x].key.Id=l; return;}
int mid=(l+r)>>1;
if (val<=mid) Insert(tree[x].lson,val,l,mid);
else Insert(tree[x].rson,val,mid+1,r);
tree[x].key=tree[tree[x].lson].key * tree[tree[x].rson].key;
} inline int Merge(int x,int y,int l,int r)
{
if (!x || !y) return x|y;
int z=++cnt;
if (l==r) {
tree[z].key=tree[x].key+tree[y].key;
return z;
}
int mid=(l+r)>>1;
tree[z].lson=Merge(tree[x].lson,tree[y].lson,l,mid);
tree[z].rson=Merge(tree[x].rson,tree[y].rson,mid+1,r);
tree[z].key=tree[tree[z].lson].key * tree[tree[z].rson].key;
return z;
} inline Pa Query(int x,int l,int r,int L,int R)
{
if (!x) return MP(0,0);
if (L<=l && R>=r) return tree[x].key;
int mid=(l+r)>>1;
if (R<=mid) return Query(tree[x].lson,l,mid,L,R);
else if (L>mid) return Query(tree[x].rson,mid+1,r,L,R);
else return Query(tree[x].lson,l,mid,L,mid) * Query(tree[x].rson,mid+1,r,mid+1,R);
} inline int Get(int l,int r)
{
int Len=r-l+1,x=pos[r];
for (int i=20; i>=0; i--)
if (len[father[i][x]]>=Len)
x=father[i][x];
return x;
} int main()
{
scanf("%s",S+1); N=strlen(S+1);
for (int i=1; i<=N; i++) Extend(S[i]-'a'),pos[i]=last;
Extend(26);
M=read();
for (int j=1; j<=M; j++) {
scanf("%s",s+1); int le=strlen(s+1);
for (int i=1; i<=le; i++) {
Extend(s[i]-'a'),Insert(roots[last],j,1,M);
}
Extend(26);
} Sort(); for (int i=sz; i>=1; i--) {
int x=id[i];
if (par[x]) roots[par[x]]=Merge(roots[par[x]],roots[x],1,M);
} for (int i=1; i<=sz; i++) father[0][i]=par[i]; for (int j=1; j<=20; j++)
for (int i=1; i<=sz; i++)
father[j][i]=father[j-1][father[j-1][i]]; Q=read();
while (Q--) {
int l=read(),r=read(),pl=read(),pr=read();
int x=Get(pl,pr);
Pa ans=Query(roots[x],1,M,l,r);
if (!ans.Max) printf("%d %d\n",l,0);
else printf("%d %d\n",ans.Id,ans.Max);
} return 0;
}
【Codeforces666E】Forensic Examination 后缀自动机 + 线段树合并的更多相关文章
- cf666E. Forensic Examination(广义后缀自动机 线段树合并)
题意 题目链接 Sol 神仙题Orz 后缀自动机 + 线段树合并 首先对所有的\(t_i\)建个广义后缀自动机,这样可以得到所有子串信息. 考虑把询问离线,然后把\(S\)拿到自动机上跑,同时维护一下 ...
- BZOJ3413: 匹配(后缀自动机 线段树合并)
题意 题目链接 Sol 神仙题Orz 后缀自动机 + 线段树合并... 首先可以转化一下模型(想不到qwq):问题可以转化为统计\(B\)中每个前缀在\(A\)中出现的次数.(画一画就出来了) 然后直 ...
- [Luogu5161]WD与数列(后缀数组/后缀自动机+线段树合并)
https://blog.csdn.net/WAautomaton/article/details/85057257 解法一:后缀数组 显然将原数组差分后答案就是所有不相交不相邻重复子串个数+n*(n ...
- 模板—字符串—后缀自动机(后缀自动机+线段树合并求right集合)
模板—字符串—后缀自动机(后缀自动机+线段树合并求right集合) Code: #include <bits/stdc++.h> using namespace std; #define ...
- 【BZOJ4556】[TJOI2016&HEOI2016] 字符串(后缀自动机+线段树合并+二分)
点此看题面 大致题意: 给你一个字符串\(s\),每次问你一个子串\(s[a..b]\)的所有子串和\(s[c..d]\)的最长公共前缀. 二分 首先我们可以发现一个简单性质,即要求最长公共前缀,则我 ...
- bzoj5417/luoguP4770 [NOI2018]你的名字(后缀自动机+线段树合并)
bzoj5417/luoguP4770 [NOI2018]你的名字(后缀自动机+线段树合并) bzoj Luogu 给出一个字符串 $ S $ 及 $ q $ 次询问,每次询问一个字符串 $ T $ ...
- CF 666E Forensic Examination——广义后缀自动机+线段树合并
题目:http://codeforces.com/contest/666/problem/E 对模式串建广义后缀自动机,询问的时候把询问子串对应到广义后缀自动机的节点上,就处理了“区间”询问. 还要处 ...
- CF666E Forensic Examination(后缀自动机+线段树合并)
给你一个串S以及一个字符串数组T[1..m],q次询问,每次问S的子串S[pl..pr]在T[l..r]中的哪个串里的出现次数最多,并输出出现次数. 如有多解输出最靠前的那一个. 我们首先对m个字符串 ...
- [CF666E]Forensic Examination:后缀自动机+线段树合并
分析 用到了两个小套路: 使用线段树合并维护广义后缀自动机的\(right\)集合. 查询\(S[L,R]\)在\(T\)中的出现次数:给\(T\)建SAM,在上面跑\(S\),跑到\(R\)的时候先 ...
随机推荐
- Linux命令(二)关机重启
- 5个经典的javascript面试问题
问题1:Scope作用范围 考虑下面的代码: (function() { var a = b = 5;})(); console.log(b); 什么会被打印在控制台上? 回答 上面的代码会打印 ...
- 从简单类型到复杂类型的参数传递用例,以及传递简单string类型的解决办法
一,简单类型的传值 比如 public Users Get(int id) ,它可以使用两种方式获取: api/default/5 $.get("/api/default" ...
- 20155321 2016-2017-2 《Java程序设计》第五周学习总结
20155321 2016-2017-2 <Java程序设计>第五周学习总结 教材学习内容总结 第八章 异常处理 Java提供特有的语句进行处理 try { 需要被检测的代码; } cat ...
- [BZOJ 1879][SDOI 2009]Bill的挑战 题解(状压DP)
[BZOJ 1879][SDOI 2009]Bill的挑战 Description Solution 1.考虑状压的方式. 方案1:如果我们把每一个字符串压起来,用一个布尔数组表示与每一个字母的匹配关 ...
- 查看IP以及连接数
AWK: time awk 'BEGIN{while("netstat -an"|getline){if( $5 ~ /[1-255]/){split($5,t1,":& ...
- MySQL binlog导入失败
一个同事问我,说他用innobackupex恢复数据后用mysqlbinlog导入增量数据时,发现数据没有导入进去并且也没有报错. mysqlbinlog /u01/mysql_py/database ...
- eclipse中 EAR Libraries 是什么?
eclipse中 EAR Libraries 是 开发EJB工程所需的库包. 由于新建web工程时,eclipse并不能智能化的判断是否该项目以后会用到ejb, 所以为了全面考虑 就已经帮用户导入了E ...
- ajax调用WebService 不能跨域
http://www.cnblogs.com/dojo-lzz/p/4265637.html "Access-Control-Allow-Origin":'http://local ...
- Selenium Books
Recently, some of my projects rely heavily upon tests with selenium. Some books about selenium are c ...