kmp

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

 1 #include<stdio.h>
 2 #include<string.h>
 3 #define N 1000005
 4 char s[N];
 5 char p[N];
 6 int next[N];
 7 int m,n;
 8 void getnext()
 9 {
10     int j=0,k=-1;
11     next[0]=-1;
12     while(j<m)
13     {
14         if(k==-1||p[j]==p[k])
15         {
16             j++;
17             k++;
18             next[j]=k;
19         }
20         else
21             k=next[k];
22     }
23 }
24 int kmp()
25 {
26     int i=0,j=0,ans=0;
27     getnext();
28     while(i<n)
29     {
30         if(j==-1||s[i]==p[j])
31         {
32             i++;
33             j++;
34         }
35         else
36             j=next[j];
37         if(j==m)
38             ans++;
39     }
40     return ans;
41 }
42 int main()
43 {
44     int t;
45     scanf("%d",&t);
46     while(t--)
47     {
48         scanf(" %s %s",&p,&s);
49         m=strlen(p);
50         n=strlen(s);
51         printf("%d\n",kmp());
52     }
53     return 0;
54 }

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