Generate Uniqeu Random Integer List

/*
 * File:   main.cpp
 * Author: kaucsenta
 *
 * Created on 2013. november 1., 0:19
 */

#include <iostream>
#include <cstdlib>
#include <fstream>
#include <sstream>
#include <vector>

using namespace std;

int main() {
    srand (time(NULL));
    int N;
    int newitem;
    vector<int> array;
    string file;
    cout<<"Hany elemu random int listat akarsz?"<<endl;
    cin>>N;
    file="random"+static_cast<ostringstream*>( &(ostringstream() << N) )->str()+".txt";
    ofstream myfile(file.c_str());

    for(int i=0;i<N;i++){
    bool unique;
    do
    {
      unique=true;
      newitem=rand()%N;
      for(int i1=0;i1<i;i1++)
      {
         if(array[i1]==newitem)
         {
           unique=false;
            break;
         }
      }
    }while(!unique);
    array.push_back(newitem);
    cout<<array[i]<<endl;
    }
    N=array.size();
    for( vector<int>::const_iterator i = array.begin(); i != array.end()-1; ++i)
    myfile<< *i <<endl;
    myfile<<array[N-1];

myfile.close();
return 0;
}