求解

什么问题都不说，比考官还大牌！

我在VC6.0上试了没错啊。你输入了什么能给我看看吗？
#include <iostream>
#include <vector>
#include <string>
#include <set>
using namespace std;
int main ()
{
     vector<string> svec;
     string book;
     cout<<"Enter the book(ctrl+z to end):"<<endl;
     while(cin>>book)
       svec.push_back(book);
     cin.clear();
     cin.sync();
     set<string> iset;
     cout<<"choose the book you will read(ctrl+z to end):"<<endl;
     while(cin>>book){
       vector<string>::iterator iter=svec.begin();
       while(iter!=svec.end())
       {
           if(*iter==book)
           {
               iset.insert(book);
               svec.erase (iter);
               --iter;
               break;
           }
           else
               ++iter;
       }
      if(iter==svec.end())
          cout<<"no book in your plan:"<<book<<endl;
     }
}