static void Main(string[] args) { var book = new Book("Pedro's grade book"); Console.Clear(); Console.WriteLine("Welcome to GradeBook"); while (true) { Console.WriteLine("Enter a grade and press enter or enter 'q' to compute statistics and quit"); string input = Console.ReadLine(); if (input.ToLower() == "q" && book.HasGrades()) { Console.Clear(); break; } else if (input.ToLower() == "q") { Console.Clear(); Console.WriteLine("Please enter at least one grade"); continue; } try { var grade = double.Parse(input); book.AddGrade(grade); Console.Clear(); Console.WriteLine($"Grade Added: {input}"); } catch (ArgumentException ex) { Console.Clear(); Console.WriteLine(ex.Message); } catch (FormatException ex) { Console.Clear(); Console.WriteLine(ex.Message); } } var stats = book.GetStatistics(); Console.WriteLine("Here are your statistics:"); Console.WriteLine($"The lowest grade is {stats.Low}"); Console.WriteLine($"The highest grade is {stats.High}"); Console.WriteLine($"The average grade is {stats.Average:N2}"); Console.WriteLine($"The letter grade is {stats.Letter}"); }