C#: Calculate the perimeter and area of a circle

Last update on December 20 2024 12:48:45 (UTC/GMT +8 hours)

Write a C# Sharp program that takes the radius of a circle as input and calculates the perimeter and area of the circle.

JavaScript: Area and circumference of a circle

In geometry, the area enclosed by a circle of radius r is πr2. Here the Greek letter π represents a constant, approximately equal to 3.14159, which is equal to the ratio of the circumference of any circle to its diameter.

The circumference of a circle is the linear distance around its edge.

Why is the area of a circle of a circle pi times the square of the radius?

Sample Solution:-

C# Sharp Code:

using System;

public class Exercise5
{
    public static void Main()
    {
        // Declaration of variables
        double r, per_cir;
        double PI = 3.14; // Constant representing the value of Pi

        // Prompting user to input the radius of the circle
        Console.WriteLine("Input the radius of the circle : ");
        r = Convert.ToDouble(Console.ReadLine()); // Reading user input for radius

        // Calculating the perimeter of the circle using the formula: perimeter = 2 * PI * radius
        per_cir = 2 * PI * r;

        // Displaying the calculated perimeter of the circle
        Console.WriteLine("Perimeter of Circle : {0}", per_cir);

        Console.Read(); // Keeping console window open until user input to exit
    }
}

Sample Output:

Input the radius of the circle :                                                                            
25 

Perimeter of Circle : 157 

Flowchart:

C# Sharp Code Editor:

Click to Open Editor

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