static int Main(string[] args) { int year; if (args.Length != 1 || !int.TryParse(args[0], out year) || year <Astronomy.MinYear || year> Astronomy.MaxYear) { Console.WriteLine("ERROR: Must provide year {0}..{1} on command line.", Astronomy.MinYear, Astronomy.MaxYear); return(1); } SeasonsInfo seasons = Astronomy.Seasons(year); Console.WriteLine("March equinox : {0}", seasons.mar_equinox); Console.WriteLine("June solstice : {0}", seasons.jun_solstice); Console.WriteLine("September equinox : {0}", seasons.sep_equinox); Console.WriteLine("December solstice : {0}", seasons.dec_solstice); return(0); }