Skip to main content

C++ program to define a class circle to represent circles. Add a data member radius to store the radius of a circle. Write member functions area() and perimeter() to compute the area and perimeter of a circle.

 C++ program to define a class circle to represent circles. Add a data member radius to store the radius of a   circle. Write member functions area() and perimeter() to compute the area and perimeter of a circle.

    To define a Circle class in C++, we start by declaring the class with the class keyword, followed by the name of the class. In this case, we'll call it Circle. We'll then define a private data member to store the radius of the circle. Here's the code to do that:

  class Circle {
    private:
    double radius;
  };
   

    Next, we need to define public member functions that can set and get the value of the radius, as well as calculate the area and perimeter of the circle. Here's the full code for the Circle class:

    
class Circle {
  private:
    double radius;
  public:
    void setRadius(double r) {
        radius = r;
    }
    double getRadius() {
        return radius;
    }
    double area() {
        return 3.14159 * radius * radius;
    }
    double perimeter() {
        return 2 * 3.14159 * radius;
    }
};

       

As you can see, we've defined four public member functions for the Circle class:

  • setRadius() sets the value of the radius to a given value.
  • getRadius() returns the current value of the radius.
  • area() calculates and returns the area of the circle using the formula Ï€r².
  • perimeter() calculates and returns the perimeter of the circle using the formula 2Ï€r.

      

Using the Circle class to calculate area and perimeter

Now that we have defined the Circle class, we can use it to calculate the area and perimeter of a circle of a given radius. Here's the full code for a C++ program that uses the Circle class to calculate the area and perimeter of a circle with radius 5.0:

    
#include 
using namespace std;

class Circle {
  private:
    double radius;
  public:
    void setRadius(double r) {
        radius = r;
    }
    double getRadius() {
        return radius;
    }
    double area() {
        return 3.14159 * radius * radius;
    }
    double perimeter() {
        return 2 * 3.14159 * radius;
    }
};

int main() {
  Circle c;
  c.setRadius(5.0);
  cout << "Radius: " << c.getRadius() << endl;
  cout << "Area: " << c.area() << endl;
  cout << "Perimeter: " << c.perimeter() << endl;
  return 0;
}


       

    In this program, we first create an instance of the Circle class called c. We then set the radius of the circle to 5.0 using the setRadius() function. Finally, we use the getRadius(), area(), and perimeter() functions to print out the radius, area, and perimeter of the circle.

Comments

Popular posts from this blog

C Program to find out the roots of a Quadratic Equation and also test for Real and Complex roots

 C Program to find out the roots of a Quadratic Equation  and also test for Real and Complex roots.       In this example, we will calculate the roots of the quadratic equation by testing for real and complex roots. We can test real and complex roots by checking these conditions : If b 2  −4 ac  < 0, then there are no real roots. If b 2  −4 ac  = 0, then both the roots are equal. If b 2  −4 ac  > 0, then roots are real and distinct.   PROGRAM TO FIND OUT THE ROOTS OF A QUADRATIC EQUATION. #include <stdio.h> #include <conio.h> #include <math.h> int   main () {      int   a , b , c , d ;      float   x , y ;      printf ( "Enter coefficient of x^2,x and constant : " );      scanf ( " %d   %d   %d " ,& a ,& b ,& c );      d = b * b ...

C Program to Multiply two Matrices

 C Program to Multiply two Matrices.     In this example, we will calculate the product of the two matrices allowing the user to enter their required number of rows and columns. In matrix multiplication the number of columns, in the first matrix must be equal to the number of  rows in the second matrix, otherwise multiplication is not possible. The product will have the number of rows of the first matrix and the number of columns of the second matrix.     Here in the output we have taken two matrices of order 2x3 and 3x2. The resulting matrix after calculating the product will be of the order 2x2. PROGRAM #include <stdio.h> #include <conio.h> void   main () {      int   row1 , row2 , column1 , column2 , i , j , k ;      int   a [ 10 ][ 10 ], b [ 10 ][ 10 ], mul [ 10 ][ 10 ];      printf ( "Enter the row size of the 1st Matrix :...

C Program to Check whether a given number is Perfect or Not

 C Program to Check whether a given number is Perfect or Not. In this exmaple we will learn to check a given number is a Perfect Number or not.  LOGIC OF PERFECT SQUARE NUMBER: At first we have declared variables i , num , sum=0 (value is initialized to zero).  Then we have inputted the number from the user and stored in num. After that we have to to add a loop i=1 till num/2 and to increment the iteration by 1. You all must be thinking why we have to run the loop till n um/2 because a number does not have any positive integer greater than the half of the number that is num/2 . Then we have to check whether the remainder of num%i is equal to zero or not. If it is equal then the value of i is a proper divisor of the number entered by the user and it is added to sum. Now we have to check if the sum of the proper divisors of the number equal to the original number. If it is equal then the number entered by the user is a perfect number otherwise it is not a perfect num...

C Program to Add Two Matrices Using Multi-dimensional Array.

C Program to Add Two Matrices Using Multi-dimensional Array.       In this example, we will add two matrices using multi-dimensional array. Two matrices can be added if they are equal means their order/dimensions must be same. Addition of matrices is performed by adding the corresponding elements of the two matrices.     Here in the Output we have  allowed the user to enter the row and column size of their matrices according to their requirements but they can enter the value of row size and column size less than 100. PROGRAM #include <stdio.h> #include <conio.h> int   main () {      int   row , column , i , j , a [ 100 ][ 100 ], b [ 100 ][ 100 ], c [ 100 ][ 100 ];      printf ( "Enter the row size of the matrices(max. value 100) : " );      scanf ( " %d " ,& row );      printf ( "Enter the co...

C program to read m x n matrix and calculate the Row sum and Column sum of the matrix.

 C program to read m x n matrix and calculate the Row sum and Column sum of the matrix.     In this example, we read a m x n matrix whose value would be entered by the user then the sum of row and column is calculated. Here in the example we have taken a matrix of order 3 x 2 whose row sum and column sum is displayed in the output screen. PROGRAM TO READ m x n MATRIX AND CALCULATE THE ROW SUM AND COLUMN SUM OF THE MATRIX: #include <stdio.h> #include <conio.h> void  main() {      int  i,j,m[100][100],row,column,rsum,csum=0;     printf( "Enter the row size of the matrix :" );     scanf( "%d" ,&row);     printf( "Enter the column size of the matrix :" );     scanf( "%d" ,&column);     printf( "Enter the Matrix : " );    ...