POJ2406 Power Strings

 1 #include<set>
 2 #include<queue>
 3 #include<cstdio>
 4 #include<cstdlib>
 5 #include<cstring>
 6 #include<iostream>
 7 #include<algorithm>
 8 using namespace std;
 9 const int N = 1000010;
10 #define For(i,n) for(int i=1;i<=n;i++)
11 #define Rep(i,l,r) for(int i=l;i<=r;i++)
12 char s[N];
13 int next[N],n;
14 
15 void BuildNext(char s[]){
16     next[0]=next[1]=0;
17     For(i,n-1){
18         int j=next[i];
19         while(j&&s[i]!=s[j]) j=next[j];
20         if(s[i]==s[j])  next[i+1]=j+1;
21         else            next[i+1]=0;
22     }
23 }
24 
25 int main(){
26     while(scanf("%s",&s),s[0]!=‘.‘){
27         n=strlen(s);BuildNext(s);
28         int rpt = n-next[n];
29         int i = n;
30         while(i&&i-next[i]==rpt) i=next[i];
31         if(i) printf("1\n");
32         else  printf("%d\n",n/rpt);
33     }
34     return 0;
35 }