题面

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 word W and a text T, count the number of occurrences of W in T. All the consecutive characters of W must exactly match consecutive characters of T. 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 word W, a string over {'A', 'B', 'C', …, 'Z'}, with 1 ≤ |W| ≤ 10,000 (here |W| denotes the length of the string W).

One line with the text T, 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 word W in the text T.

Sample Input

3

BAPC

BAPC

AZA

AZAZAZA

VERDI

AVERDXIVYERDIAN

Sample Output

1

3

0

题解

这是一道KMP模板题

我竟然Wa了N遍才AC（实测N=4）

题目大意：给你T组字符串，问第一个串在第二个中出现了几次

KMP太毒了，，，，老是写Wa。。。。

滑稽

这一道题用来复习KMP

#include<iostream>

#include<cstdio>

#include<cstdlib>

#include<cstring>

#include<cmath>

#include<algorithm>

using namespace std;

#define Next nt

char a[1000100],b[1000100];

int nt[1000100];

inline void getnext()//获得字符串s的next数组

{

    int l=strlen(a),t;

    Next[0]=-1;//如果在0位置失配则是向下移动一位

    for(int i=1;i<l;++i)//依次求解后面的next数组

    {

        t=Next[i-1];

        while(a[t+1]!=a[i]&&t>=0)

            t=Next[t];

        if(a[t+1]==a[i])

            Next[i]=t+1;

        else

            Next[i]=-1;

    }

}

int KMP()

{

	   int l=strlen(b);

	   int l2=strlen(a);

	   int i=0,j=0;//匹配指针

	   int sum=0;

	   while(i<l)

	   {

	   	       if(a[j]==b[i])

	   	       {

	   	       	     j++;i++;

	   	       	     if(j==l2)//匹配完了

					 {

					 	    ++sum;

					 	    j=nt[j-1]+1;

					 }

	   	       }

	   	       else//失配

	   	       {

	   	       	     if(j==0)//首位失配

						   i++;

					 else//跳转

					    j=nt[j-1]+1;

	   	       }

	   }

	   return sum;

}

int main()

{

	int T;

	cin>>T;

	while(T--)

	{

    	scanf("%s",a);

    	scanf("%s",b);

    	//memset(nt,0,sizeof(nt));

    	getnext();

    	cout<<KMP()<<endl;

    }

    return 0;

}