Period(KMP,循环节问题）

#include <map>
#include <set>
#include <list>
#include <cmath>
#include <queue>
#include <stack>
#include <cstdio>
#include <vector>
#include <string>
#include <cctype>
#include <complex>
#include <cassert>
#include <utility>
#include <cstring>
#include <cstdlib>
#include <iostream>
#include <algorithm>
using namespace std;
typedef pair<int,int> PII;
typedef long long ll;
#define lson l,m,rt<<1
#define pi acos(-1.0)
#define rson m+1,r,rt<<11
#define All 1,N,1
#define read freopen("in.txt", "r", stdin)
const ll  INFll = 0x3f3f3f3f3f3f3f3fLL;
const int INF= 0x7ffffff;
const int mod =  1000000007;
int n,next[1000001];
char s[10000001];
void getNext(){
    next[0]=-1;
    int i=0,j=-1;
    while(i<n){
        if(j==-1||s[i]==s[j]){
            i++;
            j++;
            next[i]=j;
        }
        else j=next[j];
    }
}
int main()
{
    int num=0;
    while(~scanf("%d",&n)){
        if(n==0)break;
        scanf("%s",s);
        printf("Test case #%d\n",++num);
        getNext();
        for(int i=1;i<=n;++i){
            if(i%(i-next[i])==0&&next[i]!=0)
                printf("%d %d\n",i,i/(i-next[i]));
        }
        printf("\n");
    }
return 0;
}