hdu 1439 Cipher(置换群)

 1 #include<bits/stdc++.h>
 2 #define F(i,a,b) for(int i=a;i<=b;++i)
 3 using namespace std;
 4 
 5 const int N=300;
 6 char s[N],ans[N];
 7 int a[N],rep[N],n,k;
 8 
 9 int main()
10 {
11     while(scanf("%d",&n),n)
12     {
13         F(i,1,n)scanf("%d",a+i),rep[i]=0;
14         F(i,1,n)
15         {
16             int now=i;
17             while(now!=i||!rep[i])now=a[now],rep[i]++;
18         }
19         while(scanf("%d",&k),k)
20         {
21             getchar();
22             gets(s+1);
23             int flag=0;
24             F(i,1,n)
25             {
26                 if(s[i]==0)flag=1;
27                 int now=i,tmp=k%rep[i];
28                 while(tmp--)now=a[now];
29                 if(flag)ans[now]=‘ ‘;
30                 else ans[now]=s[i];
31             }
32             ans[n+1]=0;
33             puts(ans+1);
34         }
35         puts("");
36     }
37     return 0;
38 }