Assignments and GDBs

CS201 C++ Assignmnet Solution 1 (13-06-2011)

Semester: Spring 2011

CS201: Introduction to Programming

Problem Statement: Circle Area & Circumference Calculation

 You are required to write a program which will calculate the area and circumference of the circle by declaring a class. You must declare a class named Circle whose only data member will be radius which should be declared as public. You need to define a macro for the value of PI which will be used while calculating the area of the circle.

Detailed Description:

 Data member radius should be of type double and it should be declared under public scope.

• Value for PI should be defined using #define macro.

 Your class should have two type of constructors:

 1. Default Constructor which should initialize radius of the circle with value 0.

 2. User Defined Constructor which takes class data member radius as its parameter.

• Declare a public member function named CalculateArea() which calculates the area of the circle. The formula for calculating the area is.

 Declare a public member function named CalculateCircum() which calculates the circumference of the circle. The formula for calculating the circumference is.

 Declare a public member function named Display which will display the calculated area and circumference of the circle on the output screen.

 In the main() function, declare two objects of type Circle:

 One using default constructor

• Second using user-defined constructor.

 It should be Display the area and circumference of the circle on the screen like the sample output.

  Sample Output:

 Radius of the Circle = 0

Area of the Circle = 0

Circumference of the Circle is = 0

Radius of the Circle = 3.5

Area of the Circle = 38.465

Circumference of the Circle is = 21.98

Solution

/*  Solution Assignment No. 3, Spring 2011 */

//  This program calculate the area and circumference of the circle by declaring a class

//  Including header files in the program.
#include

using namespace std;
// defining a macro for the value of PI
#define PI 3.14

//  Beginning of the class Circle
class Circle {
   
   
    //  declaring public members of the class
    public:
       
       double radius;    //    only data member of the class
      
       //       declaration of public member functions of the class
      
       Circle();            //  default constructor
      
       Circle(double);       //  Parameterized constructor
      
       double CalculateArea();       // calculates area of the circle and then returns
      
       double CalculateCircum();//       calculates circumference of the circle
      
       void Display();       //       displays the area and circumference of the screen
      
};

//       end of class

//  definition of default constructor of class
Circle::Circle()      
{
    radius = 0.0;   // assignning default value to the data member radius
}

//    definition of parameterized constructor of the class
Circle::Circle(double rad)
{
    radius = rad;
}

//    definition of the function for area calculation of the circle
double Circle::CalculateArea()
{
    return (PI * radius * radius);  //  calculating area and then returning it the caller function
}

//    definition of the function for calculating circumference of the circle
double Circle::CalculateCircum()
{
    return ( 2 * PI * radius ); //  calculating and returning the circumferencr to the caller function
}

//    defintion of display() function
void Circle::Display()
{

   
    cout