Power Strings

题目连接

#include <stdio.h>
#include <algorithm>
#include <string.h>
using namespace std;

inline int read()
{
    int x=0,f=1;char ch=getchar();
    while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
    while(ch>='0'&&ch<='9'){x=x*10+ch-'0';ch=getchar();}
    return x*f;
}


/********************************************************************/

const int maxn = 2e7+7;
char s[maxn];
int Next[maxn];


int main(){
    while(~scanf("%s", s+1)){
        if(s[1] == '.') break;
        int len = strlen(s+1);
        int k = 0;
        Next[1] = 0;
        for(int i = 2;i <= len;i++){
            while(k > 0 && s[k+1] != s[i]){
                k = Next[k];
            }
            if(s[k+1] == s[i]){
                k++;
            }
            Next[i] = k;
        }

        if(len%(len-Next[len])){
            printf("1\n");
        }
        else printf("%d\n", len/(len-Next[len]));

    }
    return 0;
}