//Illustrates the difference between a call-by-value
//parameter and a call-by-reference parameter.
#include <iostream.h>

void do_stuff(int par1_value, int& par2_ref);
//par1_value is a call-by-value formal parameter and
//par2_ref is a call-by-reference formal parameter.

int main( )
{
    int n1, n2;

    n1 = 1;
    n2 = 2;
    do_stuff(n1, n2);
    cout << "n1 after function call = " << n1 << endl;
    cout << "n2 after function call = " << n2 << endl;
    return 0;
}

void do_stuff(int par1_value, int& par2_ref)
{
    par1_value = 111;
    cout << "par1_value in function call = "
         << par1_value << endl;
    par2_ref = 222;
    cout << "par2_ref in function call = "
         << par2_ref << endl;
}