#include <iostream>
using namespace std;

class IntCell
{
  public:
    explicit IntCell( int initialValue = 0 );

    IntCell( const IntCell & rhs );
    ~IntCell( );
    const IntCell & operator=( const IntCell & rhs );

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

IntCell::IntCell( int initialValue )
{
    storedValue = new int( initialValue );
}

IntCell::IntCell( const IntCell & rhs )
{
    storedValue = new int( *rhs.storedValue );
}

IntCell::~IntCell( )
{
    delete storedValue;
}

const IntCell & IntCell::operator=( const IntCell & rhs )
{
    if( this != &rhs )
        *storedValue = *rhs.storedValue;
    return *this;
}

int IntCell::read( ) const
{
    return *storedValue;
}

void IntCell::write( int x )
{
    *storedValue = x;
}

/*
 * Figure 1.15.
 */
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;
}