标签：stream time one single over splay find man class
| Time Limit: 1000MS | Memory Limit: 65536K | |
| Total Submissions: 40443 | Accepted: 16266 |
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:
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
Source
#include<cstdio> #include<cstring> #include<algorithm> #include <iostream> #include <string> using namespace std; int next[ 100010]; char a[1000100],b[100010]; int lena,lenb; void get_next() { memset(next,0,sizeof(next)); for(int i=1;i<lenb;i++) { int j=next[i]; while(j&&b[i]!=b[j]) j=next[j]; next[i+1]=(b[i]==b[j])?j+1:0; } } int kmp() { int ans=0; int j=0; for(int i=0;i<lena;i++) { while(j&&a[i]!=b[j]) j=next[j]; if(a[i]==b[j]) j++; if(j==lenb) ans++; } return ans; } int main() { int T; scanf("%d",&T); while(T--) { scanf("%s%s",b,a); lena=strlen(a); lenb=strlen(b); get_next(); int ans=kmp(); printf("%d\n",ans); } return 0; }
标签：stream time one single over splay find man class
原文地址：http://www.cnblogs.com/asuml/p/6895556.html
