POJ 3461 Oulipo

D - Oulipo

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

Submit Status Practice POJ 3461

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<algorithm>#include<cstdio>#include<cstring>using namespace std;#define maxn 1005#define inf 0x3f3f3f3ftypedef long long ll;char w[maxn],t[maxn];int f[maxn];int ans;void getfail(){    int m=strlen(w);    f[0]=0;    f[1]=0;    for(int i=1;i<m;i++){        int j=f[i];        while(j&&w[i]!=w[j])j=f[j];        f[i+1]=w[i]==w[j]?j+1:0;    }}void match(){   int m=strlen(w);   int n=strlen(t);   getfail();   int j=0;   for(int i=0;i<n;i++){    while(j&&w[j]!=t[i])j=f[j];    if(w[j]==t[i])j++;    if(j==m){        ans++;        j=f[j];    }   }}int main(){    int tt;    freopen("in.txt","r",stdin);    scanf("%d",&tt);    while(tt--){        scanf("%s %s",w,t);        ans=0;        match();        printf("%d\n",ans);    }}