Small Test of C ++ polymorphism ~!

An important feature of C ++ object-oriented is polymorphism. The following Code demonstrates the polymorphism feature. Appendix:

The following is the program source code:

# Include <iostream>

Using namespace STD;

Class shape
{
// Question requirements
Public:
Virtual double area () = 0;
Virtual void printshapename () = 0;
};

// Declare circle class
Class circle: Public shape
{
Public:
Circle ();
Circle (int r );
Circle (const circle & CIR );
Public:
Virtual double area ();
Virtual void printshapename ();
PRIVATE:
Double _ R;
};

// Declare triangle class
Class triangle: Public shape
{
Public:
Triangle ();
Triangle (INT height, int width );
Triangle (const triangle & TRI );
Public:
Virtual double area ();
Virtual void printshapename ();
PRIVATE:
Double _ height;
Double _ width;
};

 

// Declare rectangle
Class rectangle: Public shape
{
Public:
Rectangle ();
Rectangle (INT length, int width );
Rectangle (const rectangle & TRI );
Public:
Virtual double area ();
Virtual void printshapename ();
PRIVATE:
Double _ length;
Double _ width;
};

// Declare Square
Class square: Public shape
{
Public:
Square ();
Square (INT length );
Square (const square & CIR );
Public:
Virtual double area ();
Virtual void printshapename ();
PRIVATE:
Double _ length;
};

 

 

// Class circle
Circle: Circle ()
: _ R (0.0)
{
// Empty
}

Circle: Circle (int r)
: _ R (r)
{
// Empty
}

Circle: Circle (const circle & CIR)
: _ R (CIR. _ r)
{
// Empty
}

Double Circle: Area ()
{
Return _ r * 3.14159;
}

Void circle: printshapename ()
{
Cout <"this is a circle" <Endl;
}

// Class triangle
Triangle: triangle ()
: _ Height (0.0)
, _Width (0.0)
{
// Empty
}

Triangle: triangle (INT height, int width)
: _ Height (height)
, _ Width (width)
{
// Empty
}

Triangle: triangle (const triangle & TRI)
: _ Height (TRI. _ height)
, _ Width (TRI. _ width)
{
// Empty
}

Double Triangle: Area ()
{
Return _ height * _ width/2;
}

Void triangle: printshapename ()
{
Cout <"this is a triangle" <Endl;
}

 

 

// Class rectangle
Rectangle: rectangle ()
: _ Length (0.0)
, _Width (0.0)
{
// Empty
}

Rectangle: rectangle (INT length, int width)
: _ Length (length)
, _ Width (width)
{
// Empty
}

Rectangle: rectangle (const rectangle & TRI)
: _ Length (TRI. _ length)
, _ Width (TRI. _ width)
{
// Empty
}

Double rectangle: Area ()
{
Return _ length * _ width;
}

Void rectangle: printshapename ()
{
Cout <"this is a rectangle" <Endl;
}

 

 

Class Trapezoidal: Public shape
{
Public:
Trapezoidal ();
Trapezoidal (INT upperlen, int lowerlen, int height );
Trapezoidal (const trapezoidal & TRI );
Public:
Virtual double area ();
Virtual void printshapename ();
PRIVATE:
Double _ upperlen;
Double _ lowerlen;
Double _ height;
};

 

Trapezoidal: trapezoidal ()
: _ Upperlen (0.0)
, _ Lowerlen (0.0)
, _ Height (0.0)
{
// Empty
}

Trapezoidal: trapezoidal (INT upperlen, int lowerlen, int height)
: _ Upperlen (upperlen)
, _ Lowerlen (lowerlen)
, _ Height (height)
{
// Empty
}

Trapezoidal: trapezoidal (const trapezoidal & TRI)
: _ Upperlen (TRI. _ upperlen)
, _ Lowerlen (TRI. _ lowerlen)
, _ Height (TRI. _ height)
{
// Empty
}

Double Trapezoidal: Area ()
{
Return (_ upperlen + _ lowerlen) * _ height/2;
}

Void Trapezoidal: printshapename ()
{
Cout <"this is a trapezoidal" <Endl;
}

// Class Square
Square: Square ()
: _ Length (0.0)
{
// Empty
}

Square: Square (INT length)
: _ Length (length)
{
// Empty
}

Square: Square (const square & CIR)
: _ Length (CIR. _ length)
{
// Empty
}

Double square: Area ()
{
Return _ length * _ length;
}

Void square: printshapename ()
{
Cout <"this is a square" <Endl;
}

 

Int main ()
{
Shape * pshape [5] = {new circle (5), New Triangle (), new rectangle (), new trapezoidal (, 5 ), new Square (7 )};
For (INT I = 0; I <5; ++ I)
{
Pshape [I]-> printshapename ();
Cout <"the area is:" <pshape [I]-> area () <Endl;
}
}

 

Engineering Environment: win7 + vs2008