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【题意】
给定n对字符串，求每组的前一个字符串在后一个字符串之中出现了几次
【输入】
第一行一个n
接下来n组数据
一组数据两行，分别是一个字符串
【输出】
对于每组数据，输出前一个字符串在后一个字符串之中出现了几次
escription
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#include <stdio.h> #include <string.h> int i,j,k,t; char p[2000000],s[2000000]; int next[2000000]; void getNext(char *p,int *next,int len ) {int j,k;next[0]=-1;j=0;k=-1;while(j<len){if(k==-1||p[k]==p[j]){k++;j++;next[j]=k;}elsek=next[k];} } int kmp(char *s,char *p)int i,j,len1,len2,k;i=0;j=-1;k=0;len1=strlen(s);len2=strlen(p);getNext(p,next,len2);while(i<len1){if(s[i]==p[j]){i++;j++;}else{j=next[j];if(j==-1){i++;j=0;}}if(j==len2)k++;}return k; } int main() {scanf("%d",&t);for(i=0;i<t;i++){scanf("%s",p);scanf("%s",s);k=kmp(s,p);printf("%d\n",k);}return 0; }
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