C# program to find Area of Circle

Program

using System;
namespace AreaOfCircle
{
    class Program
    {
        static void Main(string[] args)
        {
            float pie = 3.14f;
            float radius, area;
            Console.Write("Enter the radius of the circle:\t");
            radius = float.Parse(Console.ReadLine());
            area = pie * radius * radius;
            Console.WriteLine("Area of Circle is:\t" + area);
        }
    }
}

This C# program calculates the area of a circle based on the user-provided radius.

1. Namespace and Class Definition

• The program is inside the AreaOfCircle namespace.
• The Program class contains the Main() method where the logic is written.

2. Declaring Variables

• pie is set to 3.14f (approximate value of π).
• Two float variables, radius and area, are declared to store the user input and the computed area.

3. Taking User Input

• The program prompts the user to enter the radius.
• The input is taken as a string and converted to a float using float.Parse().

4. Calculating the Area

• The formula for the area of a circle is applied:
  [
  \text{Area} = \pi \times \text{radius}^2 ]
• The calculated area is stored in the area variable.

5. Printing the Result

• The area of the circle is displayed using Console.WriteLine().

Key Points:

• Uses float data type to handle decimal values accurately.
• Formula used: Area = π × radius × radius.
• Prompts user for input and dynamically calculates the area.
• Can be improved by using Math.PI instead of a hardcoded π value for better precision.

Output

Enter the radius of the circle: 20
Area of Circle is:      1256