A class with various constructors

Header File: Box.h

#if !defined _BOX_H_
#define _BOX_H_

class TBox
{
public:
    // Default constructor
    TBox();
    // A line
    TBox(double L);
    // A rectangle
    TBox(double L, double H);
    // A rectangular parallepiped
    TBox(double L, double H, double W);

    double TotalArea(const int n = 3) const;
    double Volume() const;
    void Properties(const int n = 3) const;
private:
    double Length;
    double Height;
    double Width;
};

#endif	// _BOX_H_

Source File: Box.cpp

#include <iostream>
#include <iomanip>
#include "Box.h"

using namespace std;

TBox::TBox()
	: Length(0.00), Height(0.00), Width(0.00)
{
}
	
// When the object is instantiated with only the length
// assign 0 to the other not used variables
TBox::TBox(double L)
	: Length(L), Height(0.00), Width(0.00)
{
}

// When the object is instantiated with two dimensions
// assign 0 to the other not used variable
TBox::TBox(double L, double H)
	: Length(L), Height(H), Width(0.00)
{
}

// This is a complete TBox object
TBox::TBox(double L, double H, double W)
	: Length(L), Height(H), Width(W)
{
}

double TBox::TotalArea(const int n) const
{
	switch(n)
	{
	case 1:
		return 0.00;
	case 2:
		return Length * Height;
	case 3:
		return 2 * ( (Length * Height) +
					 (Height * Width) +
					 (Length * Width) );
	}
	return 0.00;
}

double TBox::Volume() const
{
    return Length * Height * Width;
}

void TBox::Properties(const int n) const
{
    cout << setiosflags(ios::fixed) << setprecision(2);

    switch(n)
    {
    case 1:
        cout << "\nLine";
	cout << "\nLength = " << Length << "\n";
	break;
    case 2:
	cout << "\nRectangle";
	cout << "\nLength = " << Length;
	cout << "\nHeight = " << Height;
	cout << "\nArea   = " << TotalArea(2) << "\n";
	break;
    case 3:
	cout << "\nBox";
	cout << "\nLength = " << Length;
	cout << "\nHeight = " << Height;
	cout << "\nWidth  = " << Width;
	cout << "\nArea   = " << TotalArea(3);
	cout << "\nVolume = " << Volume() << "\n";
	break;
    }
}

Source File: Main.cpp

#include <iostream>
#include "Box.h"

using namespace std;

int main()
{
	
    cout << "Shape Properties\n";

    // An instance declared using the default constructor
    TBox Brick;
    Brick.Properties(3);

    // A line created from a box
    TBox JustALine(40.68);
    JustALine.Properties(1);

    // A rectangular object
    TBox Rectangular(28.20, 18.44);
    Rectangular.Properties(2);

    // A complete box
    TBox Solid(10.44, 10.72, 12.05);
    Solid.Properties(3);
    
    return 0;
}