Question

Circle Class Write a Circle class that has the following member variables: • radius: a double • pi: a double initialized with the value 3.14159 The class should have the following member functions: • Default Constructor. A default constructor that sets radius to 0.0. • Constructor. Accepts the radius of the circle as an argument. • setRadius. A mutator function for the radius variable. • getRadius. An accessor function for the radius variable. • getArea. Returns the area of the circle, which is calculated as area = pi * radius * radius • getDiameter. Returns the diameter of the circle, which is calculated as diameter = radius * 2 • getCircumference. Returns the circumference of the circle, which is calculated as circumference = 2 * pi * radius Write a program that demonstrates the Circle class by asking the user for the circle’s radius, creating a Circle object, and then reporting the circle’s area, diameter, and circumference. SAMPLE RUN #0: ./circle_Non-Interactive Interactive Session Standard Error (empty) Standard Output Hide Invisibles Highlight: NoneStandard Input OnlyPrompts OnlyStandard Output w/o PromptsFull Standard OutputAllShow Highlighted Only Calling·default·constructor:·The·circle's·radius·in·the·default·Circle·Object·is:·0↵ ↵ Calling·setRadius(20)·to·change·radius·of·default:↵ The·circle's·radius·in·the·default·Circle·Object·is·Now:·20↵ ↵ Creating·Circle·circle2(10):·↵ The·circle2's·radius·in·the·circle2·Object·is:·10↵ ↵ The·circle2's·area·is·therefore:·314.159↵ The·circle2's·diameter·is·therefore:·20↵ The·circle2's·circumference·is·therefore:·62.8318↵ out put must be like sample run. HELP PLEASE ANSWER IN C++

Answer 1

#include <iostream>
using namespace std;

class Circle
{
   private:
   double radius;
   double pi = 3.14159;
  
   public:

// constructors
   Circle()
   {
       radius = 0.0;
   }
   Circle(double radius)
   {
       this->radius = radius;
   }
   void setRadius(double radius)
   {
       this->radius = radius;
   }
   double getRadius()
   {
       return radius;
   }
   double getArea()
   {
       return pi*radius*radius;
   }
   double getDiameter()
   {
       return 2*radius;
   }
   double getCircumference()
   {
       return 2*pi*radius;
   }
};
  
int main() {
  
   Circle c;
   cout<<"Calling·default·constructor:";
   cout<<"\nThe·circle's·radius·in·the·default·Circle·Object·is:"<<c.getRadius();
   cout<<"\nCalling·setRadius(20)·to·change·radius·of·default:";
   c.setRadius(20);
   cout<<"\nThe·circle's·radius·in·the·default·Circle·Object·is·Now:"<<c.getRadius();
  

   cout<<"\nCreating·Circle·circle2(10):";
   Circle circle2(10);
      
   cout<<"\nThe·circle2's·radius·in·the·circle2·Object·is:"<<circle2.getRadius();
   cout<<"\nThe·circle2's·area·is·therefore:"<<circle2.getArea();
   cout<<"\nThe·circle2's·diameter·is·therefore:"<<circle2.getDiameter();
   cout<<"\nThe·circle2's·circumference·is·therefore:"<<circle2.getCircumference();
  
  
   return 0;
}

Output:

Calling·default·constructor:
The·circle's·radius·in·the·default·Circle·Object·is:0
Calling·setRadius(20)·to·change·radius·of·default:
The·circle's·radius·in·the·default·Circle·Object·is·Now:20
Creating·Circle·circle2(10):
The·circle2's·radius·in·the·circle2·Object·is:10
The·circle2's·area·is·therefore:314.159
The·circle2's·diameter·is·therefore:20
The·circle2's·circumference·is·therefore:62.8318

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