#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;
int main() 
{
   vector<int> v1, v2;
   for (int x = 1; x < 11; ++x) {
      v1.push_back(x);
      v2.push_back(2 * x);
   }

   vector<int> v3(v1.size() + v2.size());
   vector<int>::iterator middle = copy(v1.begin(), v1.end(), v3.begin());
   copy(v2.begin(), v2.end(), middle + 1);

   for (vector<int>::size_type i = 0; i < v3.size(); ++i) {
       cout << v3[i] << endl;
   }
   return 0;
}