// Program to read in integers and print in two columns.
//
// Input:  sequence of N integers read from standard input.
// Output:  input sequence of integers printed to standard output in
//            two-column format, with first column containing first 
//            (N+1)/2 numbers and second column containing remaining 
//            numbers.
//
// This version uses the STL.


#include <iostream.h>
#include <stdlib.h>		// has EXIT_SUCCESS
#include <vector>

typedef vector<int>::size_type v_size_t;


int main(void)
{
  vector<int> v;
  int temp;

  cout << "Enter some integers, control-D to end:\n";
  while (cin >> temp)
      v.push_back(temp);

  v_size_t size = v.size();		// to save a little typing

  for (v_size_t i = 0; i < size/2; ++i)
    cout << v[i] << "\t" << v[i + (size+1)/2] << endl;

  if (size % 2 != 0)
    cout << v[size/2] << endl;

  return EXIT_SUCCESS;
}