Switch Ejercicio C# - Curso de Programación C# (C Sharp)

using System;  // Import the System namespace which contains fundamental classes

class Program  // Define the Program class
{
    static void Main()  // The entry point of the program
    {
        // Ask the user to enter a numerical grade
        Console.Write("Enter the numerical grade: ");
        int grade = int.Parse(Console.ReadLine());  // Read and convert the input into an integer

        // Using 'if' to determine the corresponding grade text
        if (grade >= 9 && grade <= 10)  // Check if grade is between 9 and 10 (inclusive)
        {
            Console.WriteLine("Excellent");  // Display "Excellent" for grades 9-10
        }
        else if (grade >= 7 && grade <= 8)  // Check if grade is between 7 and 8 (inclusive)
        {
            Console.WriteLine("Very good");  // Display "Very good" for grades 7-8
        }
        else if (grade == 6)  // Check if grade is exactly 6
        {
            Console.WriteLine("Good");  // Display "Good" for grade 6
        }
        else if (grade == 5)  // Check if grade is exactly 5
        {
            Console.WriteLine("Pass");  // Display "Pass" for grade 5
        }
        else if (grade >= 0 && grade <= 4)  // Check if grade is between 0 and 4 (inclusive)
        {
            Console.WriteLine("Fail");  // Display "Fail" for grades 0-4
        }
        else  // If none of the above conditions are met, the grade is invalid
        {
            Console.WriteLine("Invalid grade");  // Display "Invalid grade" for any invalid input
        }

        // Separate the two sections with a line break
        Console.WriteLine();

        // Using 'switch' to determine the corresponding grade text
        switch (grade)  // Switch statement based on the value of 'grade'
        {
            case int n when (n >= 9 && n <= 10):  // Check if grade is between 9 and 10 (inclusive)
                Console.WriteLine("Excellent");  // Display "Excellent" for grades 9-10
                break;  // Exit the switch block after executing this case
            case int n when (n >= 7 && n <= 8):  // Check if grade is between 7 and 8 (inclusive)
                Console.WriteLine("Very good");  // Display "Very good" for grades 7-8
                break;  // Exit the switch block after executing this case
            case 6:  // Check if grade is exactly 6
                Console.WriteLine("Good");  // Display "Good" for grade 6
                break;  // Exit the switch block after executing this case
            case 5:  // Check if grade is exactly 5
                Console.WriteLine("Pass");  // Display "Pass" for grade 5
                break;  // Exit the switch block after executing this case
            case int n when (n >= 0 && n <= 4):  // Check if grade is between 0 and 4 (inclusive)
                Console.WriteLine("Fail");  // Display "Fail" for grades 0-4
                break;  // Exit the switch block after executing this case
            default:  // This block executes if no case matches
                Console.WriteLine("Invalid grade");  // Display "Invalid grade" for any invalid input
                break;  // Exit the switch block after executing this case
        }
    }
}