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.

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.

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.

 #include<iostream>

 #include<cstdio>

 #include<cstring>

 using namespace std;

 char a[];

 char b[];

 int  p[];

 int la,lb;

 int j;

 int ans;

 inline void makep()

 {

     j=;

     for(int i=;i<la;i++)

     {

         while(j>&&a[i]!=a[j])

         j=p[j];

         if(a[i]==a[j])

         j++;

         p[i]=j;

     }

     return ;

 }

 inline void KMP()

 {

     j=;

     ans=;

     for(int i=;i<lb;i++)

     {

         while(b[i]!=a[j]&&j>)

         j=p[j-];

         if(b[i]==a[j])

         j++;

         if(j==la)

         {

             ans++;

             j=p[j-];

         }

     }

     printf("%d\n",ans);

     return ;

 }

 int main()

 {

     int n;

     scanf("%d",&n);

     for(int i=;i<=n;i++)

     {

         memset(p,,sizeof(p));

         scanf("%s%s",a,b);

         la=strlen(a);lb=strlen(b);

         makep();

         KMP();

     }

     return ;

 }

AC

 #include<cstdio>

 #include<cstdlib>

 #include<cstring>

 #include<iostream>

 using namespace std;

 int n,la,lb;

 int next[];

 char a[],b[];

 void getnext()

 {

     int j=-;

     next[]=-;

     for(int i=;i<lb;i++)

     {

         if(j!=- && b[j+]!=b[i])    j=next[j];

         if(b[j+]==b[i])    j++;

         next[i]=j;

     }

 }

 int kmp()

 {

     int ans=;

     int j=-;

     for(int i=;i<la;i++)

     {

         if(j!=- && a[i]!=b[j+])    j=next[j];

         if(b[j+]==a[i])    j++;

         if(j==lb-)

         {

             ans++;

             j=next[j];

         }

     }

     return ans;

 }

 int main()

 {

     scanf("%d",&n);

     for(int u=;u<=n;u++)

     {

         scanf("%s %s",b,a);

         la=strlen(a);

         lb=strlen(b);

         getnext();

         printf("%d\n",kmp());

     }

 }