poj 3461 Oulipo（KMP）

Oulipo

Time Limit: 1000MS		Memory Limit: 65536K
Total Submissions: 49378		Accepted: 19617

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

C/C++：

 #include <map>
 #include <queue>
 #include <cmath>
 #include <vector>
 #include <string>
 #include <cstdio>
 #include <cstring>
 #include <climits>
 #include <iostream>
 #include <algorithm>
 #define INF 0x3f3f3f3f
 using namespace std;
 const int my_max = 1e6 + ;

 int my_len1, my_len2, my_next[my_max];
 char my_str1[my_max], my_str2[my_max];

 int my_kmp()
 {
     int my_cnt = ;
     memset(my_next, , sizeof(my_next));
     for (int i = , j = ; i < my_len1; ++ i)
     {
         while (j >  && my_str1[i] != my_str1[j]) j = my_next[j];
         if (my_str1[i] == my_str1[j]) ++ j;
         my_next[i + ] = j;
     }
     for (int i = , j = ; i < my_len2; ++ i)
     {
         while (j >  && my_str1[j] != my_str2[i]) j = my_next[j];
         if (my_str1[j] == my_str2[i]) ++ j;
         if (j == my_len1) my_cnt ++, j = my_next[j];
     }
     return my_cnt;
 }

 int main()
 {
     int t;
     scanf("%d", &t);
     while (t --)
     {
         scanf("%s", my_str1);
         my_len1 = strlen(my_str1);
         scanf("%s", my_str2);
         my_len2 = strlen(my_str2);

         printf("%d\n", my_kmp());
     }
     return ;
 }