How to Extend existing enums

Picked up this very interesting example on extending enum's. The program is self explanatory and is as follows:

//Program tested on Microsoft Visual Studio 2008 - Zahid Ghadialy
#include<iostream>

using namespace std;

int main()
{
  enum Enum1
  {
    value1,
    value2,
    value3,
    final_value = value3
  };

  //Print out the enum values
  cout<<"Enum1 values : ";
  for(int i = 0; i <= final_value; i++)
    cout<<Enum1(i)<<" ";
  cout<<endl;

  enum extendedEnum1
  {
    value4 = final_value + 1,
    value5,
    value6,
    new_final_value = value6
  };

  //Print out the enum values
  cout<<"extendedEnum1 values : ";
  for(int i = 0; i <= new_final_value; i++)
    cout<<extendedEnum1(i)<<" ";
  cout<<endl;

  return 0;
}

The output is as follows:

Via: Learning C++: Extending enums