poj 1026（置换群）

#include<iostream>
#include<cstring>
using namespace std;
char s[205],ans[205];
int a[205],b[205],len[205];
int n;
void transpose(){
    memset(len,0,sizeof(len));
    int i,t,tmp,cur;
    for(i=1;i<=n;i++){
        t = i;
        tmp = a[i];
        cur = 1;
        while(tmp!=t){
            tmp = a[tmp];
            cur++;
        }
        len[i] = cur;
    }
}
int main(){
    int i,j,k;
    while(cin>>n&&n){
        for(i=1;i<=n;i++){
            cin>>a[i];
        }
        transpose();
        while(cin>>k&&k){
            getchar();
            gets(s);
            for(i=strlen(s);i<n;i++){
                strcat(s," ");
            } 
            for(i=1;i<=n;i++){
                b[i] = i;
            }
            for(i=1;i<=n;i++){
                for(j=1;j<=k%len[i];j++){
                    b[i] = a[b[i]];
                }
            }
            for(i=1;i<=n;i++){
                ans[b[i]] = s[i-1];
            }
            ans[i] = '\0';
            cout<<ans+1<<endl;
        }
        cout<<endl;
    }
}