Graduation [C#]

using System;

namespace Graduation
{
    class Program
    {
        static void Main(string[] args)
        {
            string name = Console.ReadLine();
            double average = 0;
            int marksCount = 1;

            while (marksCount <= 12)
            {
                double input = double.Parse(Console.ReadLine());

                if (input >= 4.00)
                {
                    average += input;
                    marksCount++;
                }
            }

            average /= 12;

            Console.WriteLine($"{name} graduated. Average grade: {average:f2}");
        }
    }
}