HDU 1022 Train Problem I

HDU 1022 Train Problem I

很经典的题目吧，我把代码贴上来了。
考察队列和栈的基本操作，记得《算法艺术》上有讲解。
以下是我的代码：

#include < iostream >
#include < string >
#include < queue >
#include < stack >
#include < cstdio >
using   namespace  std;

int  main()
{
     /*
    freopen("data.in","r",stdin);
    freopen("data.out","w",stdout);
    // */
    
     int  n;
     while (cin >> n)
    {
         string  order1,order2;
        cin >> order1 >> order2;
        queue < char >  q;
         for ( int  i = 0 ;i < order1.size();i ++ )
            q.push(order1[i]);
        stack < char >  s;
         int  pos( 0 ),ans[ 100 ] = { 0 },ans_len( 0 );
         bool  success = true ;
         while ( ! q.empty())
        {
             if ( ! s.empty() && s.top() == order2[pos])
            {
                s.pop();
                pos ++ ;
                ans[ ++ ans_len] = 0 ;
            }
             else
            {
                s.push(q.front());
                q.pop();
                ans[ ++ ans_len] = 1 ;
            }
        }
         while ( ! s.empty())
        {
             if (s.top() == order2[pos])
            {
                s.pop();
                pos ++ ;
                ans[ ++ ans_len] = 0 ;
            }
             else
            {
                success = false ;
                 break ;
            }
        }
        
         if (success)
        {
            cout << " Yes. " << endl;
             for ( int  i = 1 ;i <= ans_len;i ++ )
                 if (ans[i] == 1 )
                    cout << " in " << endl;
                 else  cout << " out " << endl;
        }
         else  cout << " No. " << endl;
        cout << " FINISH " << endl;
    }
    
return   0 ;
}