static void Main(string[] args)
{
circle a = new circle(int.Parse(Console.ReadLine()));
a.finddia();
a.findperi();
a.findarea();
Console.WriteLine(a);
Console.ReadKey();
}
static void Main(string[] args)
{
circle c = new circle();
rectangle r = new rectangle();
driver d = new driver();
d.calculate(c);
d.calculate(r);
Console.ReadLine();
}
static void Main(string[] args)
{
double r = double.Parse(Console.ReadLine());
circle c = new circle(r);
// c.findarea();
Console.WriteLine(c);
Console.ReadKey();
}
