B - Oulipo poj 3461 （kmp 找子串的数，子串可以有重叠）

B - Oulipo

Time Limit:1000MS Memory Limit:32768KB 64bit IO Format:%I64d & %I64u

Submit Status

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 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

#include<cstdio>
#include<algorithm>
#include<cmath>
#include<string>
#include<cstring>
//#include<bits/stdc++.h>
using namespace std;
template<class T>inline T read(T&x)
{
char c;
while((c=getchar())<=32)if(c==EOF)return 0;
bool ok=false;
if(c=='-')ok=true,c=getchar();
for(x=0; c>32; c=getchar())
x=x*10+c-'0';
if(ok)x=-x;
return 1;
}
template<class T> inline T read_(T&x,T&y)
{
return read(x)&&read(y);
}
template<class T> inline T read__(T&x,T&y,T&z)
{
return read(x)&&read(y)&&read(z);
}
template<class T> inline void write(T x)
{
if(x<0)putchar('-'),x=-x;
if(x<10)putchar(x+'0');
else write(x/10),putchar(x%10+'0');
}
template<class T>inline void writeln(T x)
{
write(x);
putchar('\n');
}
//-------ZCC IO template------
const int maxn=1000001;
const double inf=999999999;
#define lson (rt<<1),L,M
#define rson (rt<<1|1),M+1,R
#define M ((L+R)>>1)
#define For(i,t,n) for(int i=(t);i<(n);i++)
typedef long long  LL;
typedef double DB;
typedef pair<int,int> P;
#define bug printf("---\n");
#define mod  1000000007
int next[maxn];
char a[maxn],b[maxn];

void getnext(char*s)
{
int i=0,j=-1;
next[0]=-1;
int len=strlen(s);
while(i<len)
{
if(j==-1||s[i]==s[j])
next[++i]=++j;
else
j=next[j];
}
}

int kmp(char*p,char*s)
{
int i=0,j=0,ans=0;
int n=strlen(p);
int m=strlen(s);
while(i<n&&j<m)
{
if(j==-1||p[i]==s[j])
i++,j++;
else
j=next[j];
if(j==m)
{
ans++;
j=next[j];//更新下次的匹配位置
}
}
return ans;
}
int main()
{
//#ifndef ONLINE_JUDGE
//freopen("in.txt","r",stdin);
//freopen("zccccc.txt","w",stdout);
//#endif // ONLINE_JUDGE
int n,m,i,j,t,k;
int T;
read(T);
while(T--)
{
scanf("%s%s",a,b);
getnext(a);
writeln(kmp(b,a));
}
return 0;
}