/*******************************************************
 Object Oriented Programming (OOP) in C++
 Author: Francesco Taurisano
 
 This script can be compiled using DEV-C++ IDE.
 Topics:
 How to create a class 
 Attributes and methods of a class
 Derived class
 Polymorphism 
 Constructor and destructor
 *******************************************************/

#include <iostream>
#include <cmath>
using namespace std;

// Defining a class
class rectangle
{
  public:
	  // Attributes of the class
	  int base, height;

	  // Method of the class
	  int area() 
	  { 
		  return base*height; 
	  }
};

// Defining a derived class from class rectangle
class rectangle2 : public rectangle
{
  public:
	  // Defining a new method for the derived class
	  int perimeter() 
	  { 
		  return (base+height)*2; 
	  }
};

// Defining another derived class from class rectangle
// Polymorphism, constructor and destructor
class right_triangle : public rectangle
{
  private:
	  // Defining a new method for the derived class right_triangle
	  float hypotenuse() 
	  { 
		  return sqrt(pow(float(base),2)+pow(float(height),2)); 
	  }
  public:
	  // Defining the method perimeter
	  float perimeter() 
	  { 
		  return (base+height+hypotenuse()); 
	  }
	  // Redefining the method area (polymorphism)
	  float area() 
	  { 
		  return (float(rectangle::area())/2);
	  }
	  // Constructor
	  right_triangle()
	   { 
		 base=0;
		 height=0;
		 cout << "The object has been initialized." << endl;
	   }
	   // Destructor
	   ~right_triangle()
	   { 
		 cout << "Object has been removed." << endl;
	   }
};

int main()
{
  rectangle shape1;
  rectangle2 shape2;
  right_triangle shape3;

  // Shape1 - Input 
  cout << "Shape1 (rectangle). Enter base: ";
  cin >> shape1.base;
  cout << "Shape1 (rectangle). Enter height: ";
  cin >> shape1.height;

  // Shape2 - Input 
  cout << "Shape2 (rectangle). Enter base:  ";
  cin >> shape2.base;
  cout << "Shape2 (rectangle). Enter height:  ";
  cin >> shape2.height;

  // Shape3 - Input 
  cout << "Shape3 (right triangle). Enter base:  ";
  cin >> shape3.base;
  cout << "Shape3 (right triangle). Enter height:  ";
  cin >> shape3.height;
  cout << endl;

  // Shape1 - Output
  cout << "Shape1. Rectangle area = " << shape1.area() << endl << endl;

  // Shape2 - Output
  cout << "Shape2. Rectangle area = " << shape2.area() << endl;
  cout << "Shape2. Rectangle perimeter = " << shape2.perimeter() << endl << endl;

  // Shape3 - Output
  cout << "Shape3. Right triangle area = " << shape3.area() << endl;
  cout << "Shape3. Right triangle perimeter = " << shape3.perimeter() << endl;

  system("pause");
  return 0;
}