02. Exam Preparation

using System;

namespace ExamPreparation
{
    class Program
    {
        static void Main(string[] args)
        {
            int badGrades = int.Parse(Console.ReadLine());
            string task = Console.ReadLine();

            int badGradesCounter = 0;
            double gradesTotal = 0;
            double tasksCount = 0;
            string lastProblem = "";

            while (task != "Enough")
            {
                double grade = double.Parse(Console.ReadLine());
                gradesTotal += grade;
                tasksCount++;

                if (grade <= 4)
                {
                    badGradesCounter++;

                    if (badGradesCounter == badGrades)
                    {
                        Console.WriteLine($"You need a break, {badGradesCounter} poor grades.");
                        break;
                    }
                }
                lastProblem = task;
                task = Console.ReadLine();
            }

            if (task == "Enough")
            {
                Console.WriteLine($"Average score: {gradesTotal / tasksCount:F2}");
                Console.WriteLine($"Number of problems: {tasksCount}");
                Console.WriteLine($"Last problem: {lastProblem}");
            }
        }
    }
}