#include <iostream.h>


class myClass
{
public:

   int x;	// Public variables


   void f1(int a)
   {
      x = a;	// Access public member variable
   }
};

class yourClass
{
public:

   void f1(myClass & p, int a)
   {
      p.x = a;	// Access public member variable
   }
};

int main(int argc, char ** argv)
{
   myClass   jam;
   yourClass butter;


   jam.x = 1234;
   cout << "main can update public variable x: " << jam.x << endl;

   butter.f1(jam, 4444);
   cout << "f1() in yourClass can update public variable x: " << jam.x << endl;

   jam.f1(7777);
   cout << "f1() in myClass can update public variable x: " << jam.x << endl;
}