public void Statistic()
        {
            Console.Clear();
            bool exit = false;

            while (!exit)
            {
                string            subId       = user.SubjectID;
                List <Assignment> assignments = handler.GetList();
                List <Teacher>    teachers    = teacherHandler.GetList(subId);
                Table             table       = new Table(90);
                table.PrintLine();
                table.PrintRow("ID", "Tên", "Số giờ dạy", "Số giờ vượt", "Số giờ chuẩn");
                table.PrintLine();
                foreach (var teacher in teachers)
                {
                    int   workTime     = handler.GetWorkTime(assignments, teacher.ID);
                    float standardTime = handler.GetStandardTime(teacher.Position);
                    float exceedTime   = (float)workTime - standardTime;
                    table.PrintRow(teacher.ID, teacher.Name, workTime.ToString(), exceedTime.ToString(), standardTime.ToString());
                }
                table.PrintLine();
                Console.WriteLine("nhấn esc để thoát");
                ConsoleKeyInfo keyInfo = Console.ReadKey();
                if (keyInfo.Key == ConsoleKey.Escape)
                {
                    Console.Clear();
                    exit = true;
                }
            }
        }