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;
}