//---------------------------------- static void Main(string[] args) { double x = 0, y = 0, r = 0; Console.WriteLine("To input co-ordinate:"); Input(ref x, ref y); try { do { Console.Write("To input r: "); r = double.Parse(Console.ReadLine()); } while (r < 0); } catch (Exception e) { Console.WriteLine(e); } Cycle c = new Cycle(x, y, r); c.View(); Console.Write("Chu vi: {0:F3}\nDien tich: {1:F3}\nKhoang cach tam giac den goc toa do: {2:F3}\n", c.Circumference(), c.Area(), c.Line()); Console.ReadKey(); }