/* Pass-by-reference and passing a pointer by value
 * are slightly different
 */

#include <iostream>
using namespace std;

// difference between pass by reference and
// passing a pointer by value.
// Pass-by-reference offers more control, in a sense.
// Any time we set the value of a, we are affecting the
// variable in the calling code whose address we were sent.
void f( int &a ) {
    a = 3;
}

// But with C, we can stop referring to the variable in the calling
// code if we assign to the pointer value. 
void g( int *a ) {
// Here is the use that is analogous to the pass-by-reference
//     *a = 3;

// Here is the alternate use
//     int *y = (int*)malloc( sizeof(int) );
//     *y = 5;
//     a = y;
//     *a = 7;
//     free(a);
}

int main () {
  int a = 1;
  cout << "Before f, a = " << a << endl;
  f( a );
  cout << "After f, a = " << a << endl;
  a = 1;
  cout << "Before g, a = " << a << endl;
  g( &a );
  cout << "After g, a = " << a << endl;
	
  return 0;
}