hdu poj Oulipo

Oulipo

Time Limit: 3000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 3572    Accepted Submission(s): 1404

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

3 BAPC BAPC AZA AZAZAZA VERDI AVERDXIVYERDIAN

 

Sample Output

1 3 0

 有点水

#include<stdio.h>
#include<string.h>
char a[1000005],b[10005];
int next[10005],stra,strb;
void get_next()
{
     next[0]=-1;
     int i=0,j=-1;
     while(i<strb)//这里要算出每一个字符的next的值，包括最后一个
     {
          if(j==-1||b[i]==b[j])
               next[++i]=++j;
          else
               j=next[j];
     }
}
int kmp()
{
     int i=-1,j=-1;
     int ans=0;
     while(i<stra)//整个a串都要扫一遍
     {

          if(j==-1||a[i]==b[j])
               i++,j++;
          else
                j=next[j];
                if(j==strb)//统计
               ans++;
     }
     return ans;
}
int main()
{
     int i,t,cnt;
     scanf("%d",&t);
     while(t--)
     {
          scanf("%s%s",b,a);
          stra=strlen(a);
          strb=strlen(b);
          get_next();
          cnt=kmp();
          printf("%d
",cnt);
     }
     return 0;
}