hdu 1358 Period

next数组

#include <cstdio>#include <cstring>#include <iostream>#include <time.h>#include <cstdlib>#include <cmath>#include <algorithm>using namespace std;int const MAXN = 1000010;char s[MAXN];int next[MAXN];inline void Get_Next(int n){    memset(next,0,sizeof(next));    for(int i = 1;i < n;i++){        int j = next[i];        while(j && s[i] != s[j]) j = next[j];        if(s[i] == s[j]) next[i + 1] = j + 1;        else next[i + 1] = 0;    }}int main(){    int T,k = 1;    while(~scanf("%d",&T)&&T){        scanf("%s",s);        int n = strlen(s);        Get_Next(n);        printf("Test case #%d\n",k++);        for(int i = 1;i <= n;i++){            if(i %(i - next[i]) == 0 && next[i])                printf("%d %d\n",i,i / (i - next[i]));        }        printf("\n");    }    return 0;}