// Ex8_03.cpp
  // Exercising the overloaded 'greater than' operator
  include <iostream>                      // For stream I/O
  using std::cout;
  using std::endl;
  
  class CBox                               // Class definition at global scope
  {
    public:
      // Constructor definition
      CBox(double lv = 1.0, double wv = 1.0, double hv = 1.0):
                                 m_Length(lv), m_Width(wv), m_Height(hv)
      {
        cout << endl << "Constructor called.";
      }
  
      // Function to calculate the volume of a box
      double Volume() const
      {
        return m_Length*m_Width*m_Height;
      }
  
      bool operator>(const CBox& aBox) const;  // Overloaded 'greater than'
  
      // Destructor definition
      ~CBox()
      {
        cout << "Destructor called." << endl;
      }
  
    private:
      double m_Length;                         // Length of a box in inches
      double m_Width;                          // Width of a box in inches
      double m_Height;                         // Height of a box in inches
  };
  
  // Operator function for 'greater than' that
  // compares volumes of CBox objects.
  bool CBox::operator>(const CBox& aBox) const
  {
    return this->Volume() > aBox.Volume();
  }
  
  int main()
  {
    CBox smallBox(4.0, 2.0, 1.0);
    CBox mediumBox(10.0, 4.0, 2.0);
    CBox bigBox(30.0, 20.0, 40.0);
  
    if(mediumBox > smallBox)
      cout << endl
           << "mediumBox is bigger than smallBox";
  
    if(mediumBox > bigBox)
      cout << endl
           << "mediumBox is bigger than bigBox";
    else
      cout << endl
           << "mediumBox is not bigger than bigBox";
  
    cout << endl;
    return 0;
  }