Period UVALive - 3026(KMP)

#include <cstdio>
#include <cstring>
#include <iostream>
#include <algorithm>
#include <cmath>
using namespace std;

const int maxn = 1000005;
char str[maxn];
int Next[maxn];
int n ;
void KMP()
{
Next[0] = 0, Next[1] = 0;
for(int i = 1; i < n; i++)
{
int j = Next[i];
while(j && str[i] != str[j]) j = Next[j];
Next[i+1] = (str[i] == str[j] ? j+1 : 0);
}
}
int main()
{
int cas = 1;
while(scanf("%d", &n) == 1 && n)
{
scanf("%s", str);
KMP();
//        for(int i =  1 ;i <= n ; i++) cout << i << " " << Next[i] << endl;
printf("Test case #%d\n", cas++);
for(int i = 2; i <= n; i++)
if(Next[i] > 0 && i % ( i - Next[i] ) == 0)
printf("%d %d\n", i, i / (i - Next[i]));
printf("\n");
}
return 0;
}