Double - C# Programming Exercise

using System;  // Import the System namespace to use basic classes like Console and Math

class Program  // Define the main class of the program
{
    static void Main()  // The entry point of the program
    {
        double width, height, perimeter, area, diagonal;  // Declare variables for width, height, perimeter, area, and diagonal

        // Ask the user for the width of the rectangle
        Console.Write("Enter the width of the rectangle: ");
        width = Convert.ToDouble(Console.ReadLine());  // Read and convert the input to double

        // Ask the user for the height of the rectangle
        Console.Write("Enter the height of the rectangle: ");
        height = Convert.ToDouble(Console.ReadLine());  // Read and convert the input to double

        // Calculate the perimeter of the rectangle
        perimeter = 2 * (width + height);  // Perimeter formula: P = 2 * (width + height)

        // Calculate the area of the rectangle
        area = width * height;  // Area formula: A = width * height

        // Calculate the diagonal of the rectangle using the Pythagorean theorem
        diagonal = Math.Sqrt(Math.Pow(width, 2) + Math.Pow(height, 2));  // Diagonal formula: d = sqrt(width^2 + height^2)

        // Display the results
        Console.WriteLine($"Perimeter: {perimeter}");  // Display the perimeter
        Console.WriteLine($"Area: {area}");  // Display the area
        Console.WriteLine($"Diagonal: {diagonal}");  // Display the diagonal
    }
}