//-----------------------------------------------------------------
//Name  :- 
//What  :- Classes and objects
//Where :- 
//When  :- 30/10/2002
//-----------------------------------------------------------------
//includes header files
#include <iostream.h>
#include <conio.h>
#include <stdio.h>
#include <stdlib.h>

//class dedfinition
class cylinder_bar
{
   public:
      cylinder_bar();               //class constructor
      void get_data(float,float);   //function for data input
      void calculate_volume();      //function to find the volume
      void calculate_surface();     //function to find the surface
      void display_results();       //function to display the results
      ~cylinder_bar();              //class destructor
   private:
      float diameter;   //declaration of the "diameter" of the class
      float height;     //declaration of the "height" of the class
      float pi;        //declaration of the "pi" of the class
      float cy_volume;  //declaration of the "volume" of the class
      float cy_surface; //declaration of the "surface" of the class
};

//default values for variables by constructor
cylinder_bar::cylinder_bar()
{
   diameter = height = cy_volume = cy_surface = 0.0;
   pi = 3.14159;
}

//this function inputs the data
void cylinder_bar::get_data(float d,float h)
{
   diameter = d;
   height = h;
}

//applies formulae for volume of cylinder
void cylinder_bar::calculate_volume()
{
   cy_volume = pi * diameter * diameter * height/4;
}

//applies formulae for surface of cylinder
void cylinder_bar::calculate_surface()
{
   cy_surface = (pi * diameter * diameter/2 + pi * diameter * height);
}

//function to display the results
void cylinder_bar::display_results()
{
   cout<<"\n The volume of the cylinder_bar is = "<<cy_volume<<endl;
   cout<<"\n The surface of the cylinder_bar is="<<cy_surface<<endl;
}

//destructor of the object
cylinder_bar::~cylinder_bar()
{
   cout<<"\n This object is destroyed. ";
}

//function header
void display_end(void) //function to display the message
{
   cout<<" The correct end of the run of that porgram! \n ";
   system("pause");
}

//defining rectangle bar class
class rect_bar
{
   public:
      rect_bar();             //class constructor
      void get_data(float);   //function for data input
      void cal_volume();      //function for volume calculation
      void cal_surface();     //function for surface calculation
      void display_results(); //function for display results
      ~rect_bar();            //class destructor
   private:
      float side_dimension;   //declaration of the side_dimension
      float volume;           //declaration of the volume
      float surface;          //declaration of the surface
};

//the constructor sets default values
rect_bar::rect_bar()
{
   side_dimension = volume = surface = 0.0;

}

//this memeber function inputs the data
void rect_bar::get_data(float a)
{
   side_dimension = a;
}

//applies the formulae to calculate the volume
void rect_bar::cal_volume()
{
   volume = (side_dimension * side_dimension )* side_dimension;
}

//applies the formullae to calculate the surface
void rect_bar::cal_surface()
{
   surface = (4.0 * side_dimension * side_dimension)
               + (2.0 * side_dimension * side_dimension) ;
}

//destructor of the class
rect_bar::~rect_bar()
{
   cout<<"\n The object is destroyed \n";
}

//displays the output as results
void rect_bar::display_results()
{
   cout<<"\n The volume of the rectangle_bar is          = "<<volume<<endl;
   cout<<"\n The surface of the rectangle_bar is         = "<<surface<<endl;
}

//follows a main function of the program that tests the cylinder_bar
//whether it fits into the cube or not and also shows the
//volume and surface of both cylinder and cube
int main()
{
   cout<<" This program calculates the volume and surface of cylinder and cube \n";
   cout<<"and displays if the cylinder fits into the cube or not.\n\n";

   cylinder_bar c;   //creates an object for the class named cylinder
   rect_bar r;       //creates an object for the class named cube
   float d,h=0.0;    //declares and initiate the variables
   cout<<"\n Enter a diameter of the cylinder_bar        = ";
   cin>>d;
   cout<<"\n Enter height of the same cylinder_bar       = ";
   cin>>h;

   c.get_data(d,h);  //inputs values for the varaibles for cylinder
   c.calculate_volume();   //calculates the volume for cylinder
   c.calculate_surface();  //calculates the surface for cylinder
   c.display_results();    //displays the results for cylinder
   c.~cylinder_bar();      //destructor function
   cout<<"\n\n";
   r.get_data(h);          //inputs values for the varaibles for cube
   r.cal_volume();         //calculates the volume for cube
   r.cal_surface();        //calculates the surface for cube
   r.display_results();    //displays the results for cube
   r.~rect_bar();          //destructor function

   if(d > h)      //if to check whether cylinder fits into the cube or not
      cout<<"\n This cylinder cannot fit into the cube. \n"<< endl;
   else
      cout<<"\n This cylinder fits into the cube. "<<endl;
   display_end();
   return 0;
}