hdu 1358 Period(kmp)

#include <cstdio>
#include <map>
#include <iostream>
#include<cstring>
#include<bits/stdc++.h>
#define ll long long int
#define M 6
using namespace std;
inline ll gcd(ll a,ll b){return b?gcd(b,a%b):a;}
inline ll lcm(ll a,ll b){return a/gcd(a,b)*b;}
int moth[13]={0,31,28,31,30,31,30,31,31,30,31,30,31};
int dir[4][2]={1,0 ,0,1 ,-1,0 ,0,-1};
int dirs[8][2]={1,0 ,0,1 ,-1,0 ,0,-1, -1,-1 ,-1,1 ,1,-1 ,1,1};
const int inf=0x3f3f3f3f;
const ll mod=1e9+7;
int nextt[1000007];
void getnext(string s){
    nextt[1]=0; int len=s.length();
    for(int i=2,j=0;i<=len;i++){
        while(j>0&&s[i-1]!=s[j]) j=nextt[j];
        if(s[i-1]==s[j]) j++;
        nextt[i]=j;
    }
}
int main(){
    ios::sync_with_stdio(false);
    int n;
    int cnt=0;
    while(cin>>n&&n){
        string s;
        cin>>s;
        getnext(s);
        int len=s.length();
        cout<<"Test case #"<<++cnt<<endl; 
        for(int i=2;i<=len;i++){
                if(nextt[i]==0) continue;
                int t=i-nextt[i];
                if(i%t==0){
                    cout<<i<<" "<<i/t<<endl;
                }
        }
        cout<<endl;
    }
    return 0;
}