class Program
    {
        static void Main(string[] args)
        {
            double r,perimeter, area;
            Console.Write("Please write the radius of your circle : ");
            r = Convert.ToDouble(Console.ReadLine());
            perimeter = 2 * 3.14 * r;
            area = 3.14 * Math.Pow(r, 2); //area = 3.14 * r * r;
            Console.WriteLine("============================================="); 
            Console.WriteLine("The perimeter of yor circle : {0}",perimeter);
            Console.WriteLine("The area of yor circle : {0}", area);
            Console.ReadKey();
        }
    }