poj 3461 Oulipo

Time Limit:1000MS		Memory Limit:65536K
Total Submissions:45636		Accepted:18224

Description

The French author Georges Perec (1936–1982) once wrote a book, La disparition, without the letter'e'. He was a member of the Oulipo group. A quote from the book:

Tout avait Pair normal, mais tout s’affirmait faux. Tout avait Fair normal, d’abord, puis surgissait l’inhumain, l’affolant. Il aurait voulu savoir où s’articulait l’association qui l’unissait au roman : stir son tapis, assaillant à tout instant son imagination, l’intuition d’un tabou, la vision d’un mal obscur, d’un quoi vacant, d’un non-dit : la vision, l’avision d’un oubli commandant tout, où s’abolissait la raison : tout avait l’air normal mais…

Perec would probably have scored high (or rather, low) in the following contest. People are asked to write a perhaps even meaningful text on some subject with as few occurrences of a given “word” as possible. Our task is to provide the jury with a program that counts these occurrences, in order to obtain a ranking of the competitors. These competitors often write very long texts with nonsense meaning; a sequence of 500,000 consecutive'T's is not unusual. And they never use spaces.

So we want to quickly find out how often a word, i.e., a given string, occurs in a text. More formally: given the alphabet {'A','B','C', …,'Z'} and two finite strings over that alphabet, a wordWand a textT, count the number of occurrences ofWinT. All the consecutive characters of W must exactly match consecutive characters ofT. Occurrences may overlap.

Input

The first line of the input file contains a single number: the number of test cases to follow. Each test case has the following format:

• One line with the wordW, a string over {'A','B','C', …,'Z'}, with 1 ≤ |W| ≤ 10,000 (here |W| denotes the length of the stringW).
• One line with the textT, a string over {'A','B','C', …,'Z'}, with |W| ≤ |T| ≤ 1,000,000.

Output

For every test case in the input file, the output should contain a single number, on a single line: the number of occurrences of the wordWin the textT.

Sample Input

3
BAPC
BAPC
AZA
AZAZAZA
VERDI
AVERDXIVYERDIAN

Sample Output

1
3
0
题意：
给你两个字符串，求第二个字符串在第一个字符串中
出现的次数。

#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cmath>
#include<cstring>
#include<string>
using namespace std;
const int N=1e6+90;
char s1[N],s2[N];
int T,len1,ans,len2,ne[N],i,j;
void kmp()
{
    for(int i=1;i<=len2;++i) ne[i]=0;
    for(int i=2;i<=len2;++i)
    {
        j=ne[i-1];
        while(j && s2[i]!=s2[j+1]) j=ne[j];
        if(s2[i]==s2[j+1]) ne[i]=j+1;
    }
    j=0;
    for(int i=1;i<=len1;++i)
    {
        while(j && s1[i]!=s2[j+1]) j=ne[j];
        if(s1[i]==s2[j+1]) j=j+1;
        if(j==len2) ans++;
    }
}
int main()
{
    scanf("%d",&T);
    while(T--)
    {
        scanf("%s%s",s2+1,s1+1);
        len1=strlen(s1+1);len2=strlen(s2+1);
        ans=0;
        kmp();
        printf("%d
",ans);
    }
    return 0;
}/*
Sample Input

3
BAPC
BAPC
AZA
AZAZAZA
VERDI
AVERDXIVYERDIAN
Sample Output

1
3
0
*/