UVALive - 3026：Period

用KMP里面的next数组即可，原理就是next数组的原理

#include<cstdio>
#include<cstdlib>
#include<algorithm>
#include<cstring>
#include<vector>
#define MAXN 1000000+10
#define ll long long
using namespace std;
char s[MAXN];
int n;
int nxt[MAXN];
void solve(){
    scanf("%s",s+1);
    memset(nxt,0,sizeof(nxt));
    nxt[1]=0;
    int k=0;
    for(int i=2;i<=n;i++){
        while(k&&s[k+1]!=s[i])k=nxt[k];
        if(s[k+1]==s[i])k++;
        nxt[i]=k;
        if(nxt[i]&&i%(i-nxt[i])==0){
            printf("%d %d\n",i,i/(i-nxt[i]));    
        }
    }
}
int main()
{
//    freopen("data.in","r",stdin);
    int T=0;
    while(1){
        scanf("%d",&n);
        if(!n)break;
        printf("Test case #%d\n",++T);
        solve();    
        printf("\n");
    }
    return 0;
}