#4CircleAreaPerimeter

using System;
class CircleAreaPerimeter
    {
        static void Main()
        {
            Console.WriteLine("Circle radius?");
            double r = double.Parse(Console.ReadLine());
            double perimeter = Math.Round((2 * (Math.PI) * r), 2);
            double area = Math.Round(((Math.PI) * (Math.Pow(r, 2))), 2);
            Console.WriteLine("Circle perimeter: {0}", perimeter);
            Console.WriteLine("Circle area: {0}", area);
        }
    }