using System;
public class LuasLingkaran
{
public static void Main(string[] args)
const float phi = 3.14f;
Console.WriteLine("== PROGRAM LUAS LINGKARAN ==");
Console.Write("Input jari-jari: ");
int r = int.Parse(Console.ReadLine());
var luas = Phi * r * r;
Console.WriteLine("Luas Lingkaran = " + luas);
}