LA 3026 Period

#include<iostream>
#include<cstring>
#include<cstdio>
#include<cstdlib>
#include<algorithm>
#define ll long long
#define maxn 1000005
using namespace std;
int f[maxn],n;
char s[maxn];
int T;
int main(){
	while(scanf("%d",&n)==1&&n){
		T++;
		printf("Test case #%d\n",T);
		
		scanf("%s",s);
		f[1]=f[0]=0;
		for(int i=1,j;i<n;i++){
			j=f[i];
			while(j&&s[i]!=s[j]) j=f[j];
			f[i+1]=(s[j]==s[i]?j+1:0);
		}
		
		for(int i=2;i<=n;i++) if(f[i])
		    if(!(i%(i-f[i]))) printf("%d %d\n",i,i/(i-f[i]));
		puts("");
	}
	
	return 0;
}