#include <iostream.h>

class Count {
   friend Count add( Count &, Count &);  // friend declaration
   friend bool equal_to( Count &, Count &);

public:
   Count() { x = 0; }                // constructor
   void print() const { cout << x << endl; }  // output
   void setX( int );		     // function of Count to set X

private:
   int x;  // data member
};

// setX is a function of class Count
void Count::setX( int val )
{
   x = val;  // legal: setX is a function of Count, 
	     // so it can access the private data member
}

// add is declared as a friend function of Count
Count add( Count &c1, Count &c2)
{
   Count temp;
   temp.x = c1.x + c2.x;
   return temp;
}

bool equal_to( Count &c1, Count &c2)
{
   if ( c1.x == c2.x)
     return true;
   else
     return false;
}

int main()
{
   Count counter1, counter2, result; 

   cout << "counter1.x after instantiation: ";
   counter1.print();

   cout << "counter2.x after instantiation: ";
   counter2.print();

   cout << "counter1.x after call to setX function: ";
   counter1.setX( 8 );  // set x with a friend
   counter1.print();

   cout << "counter2.x after call to setX function: ";
   counter2.setX( 5 );  // set x with a friend
   counter2.print();

   cout << "result.x after add counter1 and counter2 by calling add friend function: ";
   result = add(counter1, counter2);
   result.print();

   if (equal_to(counter1, counter2))
     cout << "counter1.x is equal to counter2.\n";
   else
     cout << "counter1.x is not equal to counter2.\n";
   
   return 0;
}