Calculating the Average Marks of Two Groups in C#

using System;

class Program
{
    static void Main()
    {
        // Define a 2D array for two groups of 10 students each
        int[,] marks = new int[2, 10];

        // Loop through each group
        for (int group = 0; group < 2; group++)
        {
            Console.WriteLine($"Enter marks for Group {group + 1}:");

            // Loop through each student in the group
            for (int student = 0; student < 10; student++)
            {
                Console.Write($"Student {student + 1}: ");
                
                // Read and validate input
                while (!int.TryParse(Console.ReadLine(), out marks[group, student]))
                {
                    Console.Write("Invalid input. Enter a valid mark: ");
                }
            }
        }

        // Calculate and display the average for each group
        for (int group = 0; group < 2; group++)
        {
            int sum = 0;

            for (int student = 0; student < 10; student++)
            {
                sum += marks[group, student];
            }

            double average = sum / 10.0;
            Console.WriteLine($"Average marks for Group {group + 1}: {average:F2}");
        }
    }
}

 Output

Enter marks for Group 1:
Student 1: 80
Student 2: 75
Student 3: 90
Student 4: 85
Student 5: 88
Student 6: 92
Student 7: 78
Student 8: 84
Student 9: 80
Student 10: 86

Enter marks for Group 2:
Student 1: 70
Student 2: 65
Student 3: 75
Student 4: 80
Student 5: 72
Student 6: 78
Student 7: 85
Student 8: 88
Student 9: 74
Student 10: 76

Average marks for Group 1: 83.8
Average marks for Group 2: 76.3