POJ---3461-Oulipo（KMP）

A - Oulipo

Time Limit:1000MS     Memory Limit:65536KB     64bit IO Format:%I64d & %I64u

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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

#include <iostream>#include <cstring>#include <cstdio>#include <algorithm>#define SIZE 1000000using namespace std;int next[SIZE+2];char str[SIZE+1];char poi[10001];int lena ,lenb;void get_next(){    int i=0,j=-1;    next[0]=-1;    while(i<lenb)    {        if(j==-1||str[i]==str[j])            next[++i]=++j;        else            j=next[j];    }}int main(){    int n;    cin>>n;    while(n--)    {        scanf("%s%s",poi,str);        lena=strlen(poi);        lenb=strlen(str);        get_next();        int i=0,j=0,sum=0;        while(i<lenb)        {            if(j==-1||str[i]==poi[j])            {                ++i;                ++j;            }            else                j=next[j];            if(j==lena)            {                ++sum;                j=next[j];            }        }        cout<<sum<<endl;    }    return 0;}