public override GradeStatistics ComputeStatistics()
{
GradeStatistics stats = new GradeStatistics();
float sum = 0;
foreach (float grade in grades)
{
stats.HighestGrade = Math.Max(grade, stats.HighestGrade);
stats.LowestGrade = Math.Min(grade, stats.LowestGrade);
sum += grade;
}
stats.AverageGrade = sum / grades.Count;
return(stats);
}
static void Main(string[] args)
{
IGradeTracker book = CreateGradeBook();
GetBookName(book);
WriteResults(book);
using (StreamWriter outputfile = File.CreateText("grades.txt"))
{
book.WriteGrades(outputfile);
}
GradeStatistics stats = book.ComputeStatistics();
Console.WriteLine(book.Name);
WriteResult("Highest,", stats.HighestGrade);
WriteResult("Lowest,", stats.LowestGrade);
WriteResult("Average,", stats.AverageGrade);
WriteResult(stats.Description, stats.LetterGrade);
}