POJ3461 Oulipo

Oulipo

Time Limit: 1000MS		Memory Limit: 65536K
Total Submissions: 36441		Accepted: 14728

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

Source

BAPC 2006 Qualification

问字符串2中包含多少个字符串1。

KMP匹配即可

 1 /**/
 2 #include<iostream>
 3 #include<cstdio>
 4 #include<cmath>
 5 #include<cstring>
 6 #include<algorithm>
 7 using namespace std;
 8 const int mxn=1000020;
 9 char s[mxn];
10 char a[10020];
11 int next[mxn];
12 int f[mxn];
13 int lens,lena;
14 void gne(){
15     next[0]=-1;
16     int i,j=-1;
17     for(i=1;i<lena;i++){
18         while(j>=0 && a[j+1]!=a[i])j=next[j];
19         if(a[j+1]==a[i])j++;
20         next[i]=j;
21     }
22     return;
23 }
24 int main(){
25     int T;
26     scanf("%d",&T);
27     int i,j;
28     while(T--){
29         scanf("%s%s",a,s);
30         lena=strlen(a);
31         lens=strlen(s);
32         gne();
33         j=-1;
34         int ans=0,last=0;
35         for(i=0;i<lens;i++){
36             while(j>=0 && a[j+1]!=s[i])j=next[j];
37             if(a[j+1]==s[i])j++;
38             f[i]=j;
39             if(f[i]==lena-1){
40                 ans++;
41                 j=next[j];
42             }
43         }
44         printf("%d
",ans);
45     }
46     return 0;
47 }