#include <iostream>
using namespace std;

/**
 * Figure 1.16: Implements the big five.
 */
class IntCell
{
  public:
    explicit IntCell( int initialValue = 0 )
      { storedValue = new int{ initialValue }; }

    int read( ) const
      { return *storedValue; }
    void write( int x )
      { *storedValue = x; }
    
  private:
    int *storedValue;
};


/*
 * Figure 1.17.
 */
int f( )
{
    IntCell a{ 2 };
    IntCell b = a;
    IntCell c;

    c = b;
    a.write( 4 );
    cout << a.read( ) << endl << b.read( ) << endl << c.read( ) << endl;
    
    return 0;
}


int main( )
{
    f( );
    
    return 0;
}