hdu1686

Oulipo

Time Limit: 3000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 4152    Accepted Submission(s): 1641

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

 

Source

华东区大学生程序设计邀请赛_热身赛

 

#include<iostream>#include<cstring>#include<cstdio>using namespace std;int next[10005];char str1[10005], str2[1000005];void getNext(int n){next[0] = -1;int j = -1;for(int i = 1; i < n; i++){while(j != -1&&str1[j+1]!=str1[i]){j = next[j];}if(str1[j+1]==str1[i]){j += 1;}next[i] = j;}}int kmp(int len1, int len2){int j = -1;int sum = 0;for(int i = 0; i < len2; i++){while(j!=-1&&str1[j+1]!=str2[i]){j = next[j];}if(str1[j+1]==str2[i]){j = j+1;}if(j == len1-1){sum++;j = next[j];}}return sum;}int main(){int n;cin>>n;getchar();while(n--){gets(str1);gets(str2);int len1 = strlen(str1);int len2 = strlen(str2);getNext(len1);cout<<kmp(len1, len2)<<endl;}return 0;}