Circle Area and Perimeter

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Circle_Area_and_Perimeter
{
    class Program
    {
        static void Main(string[] args)
        {
            var r = Double.Parse(Console.ReadLine());
            var area = (Math.PI*r*r);
            var perimeter = (2*Math.PI*r);
            Console.WriteLine("area=" + area );
            Console.WriteLine("perimeter=" + perimeter);
        }
    }
}