HDOJ 1686 Oulipo （KMP）

Oulipo

Time Limit: 3000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)

Total Submission(s): 7411    Accepted Submission(s): 2981

Problem 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

3BAPCBAPCAZAAZAZAZAVERDIAVERDXIVYERDIAN

 

Sample Output

130

注：此题为：HDOJ 1686 Oulipo

题意：求母串中有多少个子串，         kmp算法             模板

已AC代码：

#include<cstdio>#include<cstring>#define M 1000010int p[M];char ch[M],str[M];int len,lens,cnt;void getp()   //模板 {int i,j;i=0;j=-1;p[i]=j;while(i<len){if(j == -1 || ch[i] == ch[j]){i++,j++;p[i]=j;}elsej=p[j];}}void kmp(){getp();int i,j;i=0;j=0;while(i<lens){if(j == -1 || str[i] == ch[j]){i++,j++;if(j == len)cnt++;}elsej=p[j];}}int main(){int T;scanf("%d",&T);while(T--){scanf("%s%s",ch,str);len=strlen(ch);lens=strlen(str);cnt=0;kmp();printf("%d\n",cnt);}return 0;}