graduation part3

using System;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            string name;

            while ((name = Console.ReadLine()) != "END")
            {
                bool isStuding = true;
                double grades = 0;
                int schoolYear = 1;

                for (int i = 1; i <= 12; i++)
                {
                    double yearGrade = double.Parse(Console.ReadLine());

                    if (yearGrade < 4 )
                    {
                        if (!isStuding)
                        {
                            break;
                        }
                        isStuding = false;
                        i--;
                    }
                    else
                    {
                        grades += yearGrade;
                        schoolYear++;
                    }

                }

                if (schoolYear-1==12)
                {
                    double average = grades / 12;
                    Console.WriteLine(($"{name} graduated. Average grade: {average:F2}"));
                }
                else
                {
                    Console.WriteLine(($"{name} has been excluded at {schoolYear } grade"));
                }

            }
        }
    }
}