Codeforces 235C. Cyclical Quest 后缀自动机


将S建后缀自动机,对于每个串复制两倍的长度(2L)在自动机上跑,

统计长度为L时,对应节点的出现次数


C. Cyclical Quest
time limit per test
3 seconds
memory limit per test
512 megabytes
input
standard input
output
standard output

Some days ago, WJMZBMR learned how to answer the query "how many times does a string x occur in a string s" quickly by preprocessing the string s. But now he wants to make it harder.

So he wants to ask "how many consecutive substrings of s are cyclical isomorphic to a given string x". You are given string s and n stringsxi, for each string xi find, how many consecutive substrings of s are cyclical isomorphic to xi.

Two strings are called cyclical isomorphic if one can rotate one string to get the other one. 'Rotate' here means 'to take some consecutive chars (maybe none) from the beginning of a string and put them back at the end of the string in the same order'. For example, string "abcde" can be rotated to string "deabc". We can take characters "abc" from the beginning and put them at the end of "de".

Input

The first line contains a non-empty string s. The length of string s is not greater than 106 characters.

The second line contains an integer n (1 ≤ n ≤ 105) — the number of queries. Then n lines follow: the i-th line contains the string xi — the string for the i-th query. The total length of xi is less than or equal to 106 characters.

In this problem, strings only consist of lowercase English letters.

Output

For each query xi print a single integer that shows how many consecutive substrings of s are cyclical isomorphic to xi. Print the answers to the queries in the order they are given in the input.

Sample test(s)
input
baabaabaaa
5
a
ba
baa
aabaa
aaba
output
7
5
7
3
5
input
aabbaa
3
aa
aabb
abba
output
2
3
3


/* ***********************************************
Author        :CKboss
Created Time  :2015年06月16日 星期二 19时37分19秒
File Name     :CF235C.cpp
************************************************ */

#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include <string>
#include <cmath>
#include <cstdlib>
#include <vector>
#include <queue>
#include <set>
#include <map>

using namespace std;

/************SAM****************/

const int CHAR=27,maxn=2000200;

struct SAM_Node
{
	SAM_Node *fa,*next[CHAR];
	int len,id,pos;
	SAM_Node(){}
	SAM_Node(int _len)
	{
		fa=0; len=_len;
		memset(next,0,sizeof(next));
	}
};

SAM_Node SAM_node[maxn],*SAM_root,*SAM_last;
int SAM_size;

SAM_Node *newSAM_Node(int len)
{
	SAM_node[SAM_size]=SAM_Node(len);
	SAM_node[SAM_size].id=SAM_size;
	return &SAM_node[SAM_size++];
}

SAM_Node *newSAM_Node(SAM_Node *p)
{
	SAM_node[SAM_size]=*p;
	SAM_node[SAM_size].id=SAM_size;
	return &SAM_node[SAM_size++];
}

void SAM_init()
{
	SAM_size=0;
	SAM_root=SAM_last=newSAM_Node(0);
	SAM_node[0].pos=0;
}

void SAM_add(int x,int len)
{
	SAM_Node *p=SAM_last,*np=newSAM_Node(p->len+1);
	np->pos=len; SAM_last=np;
	for(;p&&!p->next[x];p=p->fa) p->next[x]=np;
	if(!p) { np->fa=SAM_root; return ; }
	SAM_Node *q=p->next[x];
	if(q->len==p->len+1) { np->fa=q; return ; }
	SAM_Node *nq=newSAM_Node(q);
	nq->len=p->len+1;
	q->fa=nq; np->fa=nq;
	for(;p&&p->next[x]==q;p=p->fa) p->next[x]=nq;
}

/// !!!!!!!!!!!!! 统计每个节点出现的次数

int c[maxn],num[maxn];
SAM_Node* top[maxn];

void Count(char str[],int len)
{
	for(int i=0;i<SAM_size;i++) c[SAM_node[i].len]++;
	for(int i=1;i<=len;i++) c[i]+=c[i-1];
	for(int i=0;i<SAM_size;i++) top[--c[SAM_node[i].len]]=&SAM_node[i];

	SAM_Node *p=SAM_root;
	for(;p->len!=len;p=p->next[str[p->len]-'a']) num[p->id]=1; num[p->id]=1;

	for(int i=SAM_size-1;i>=0;i--)
	{
		p=top[i];
		if(p->fa)
		{
			SAM_Node *q=p->fa; num[q->id]+=num[p->id];
		}
	}
}

/************SAM****************/

char stmain[maxn],str[maxn];
int tn;
int vis[maxn];

int READ_STR(char *str)
{
	int i=0;
	char ch;
	while(true)
	{
		ch=getchar();
		if(ch=='\n') break;
		str[i++]=ch;
	}
	str[i]=0;
	return i;
}


int main()
{
	//freopen("in.txt","r",stdin);
	//freopen("out.txt","w",stdout);

	int len=READ_STR(stmain);
	SAM_init();
	for(int i=0;i<len;i++) SAM_add(stmain[i]-'a',i+1);
	Count(stmain,len);

	scanf("%d",&tn);
	getchar();
	int cas=0;
	while(tn--)
	{
		int ans=0;
		cas++;

		int n=READ_STR(str);

		SAM_Node* cur=SAM_root;
		int nowlen=0;

		for(int i=0;i<2*n-1;i++)
		{
			if(nowlen==n)
			{
				nowlen--;
				if(nowlen<=cur->fa->len)
					cur=cur->fa;
			}

			int id=i;
			if(id>=n) id-=n;
			int to = str[id]-'a';
			while(cur!=0&&cur->next[to]==0)
			{
				cur=cur->fa;
				if(cur!=0) nowlen=cur->len;
			}
			if(cur!=0&&cur->next[to]!=0)
			{
				cur=cur->next[to];
				nowlen++;
			}
			else
			{
				cur=SAM_root;
				nowlen=0;
			}

			if(nowlen==n)
			{
				if(vis[cur->id]!=cas)
				{
					vis[cur->id]=cas;
					ans+=num[cur->id];
				}
			}
		}

		printf("%d\n",ans);
	}

    return 0;
}




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