using System; using System.Linq; using System.Reflection; namespace aoc2019 { internal static class Program { private static void Main(string[] args) { var days = Assembly.GetExecutingAssembly().GetTypes() .Where(t => t.BaseType == typeof(Day)) .Select(t => (Day) Activator.CreateInstance(t)) .OrderBy(d => d.DayNumber); if (args.Length == 1 && int.TryParse(args[0], out var dayNum)) { var day = days.FirstOrDefault(d => d.DayNumber == dayNum); if (day != null) day.AllParts(); else Console.WriteLine($"{dayNum} invalid or not yet implemented"); } else { foreach (var d in days) d.AllParts(); } } } }