PBO-C 9 : Contoh kelilinglingkaran

import java.util.Scanner;

public class kelilingLingkaran
{
    public static void main(String args[])
    {
            Scanner input = new Scanner (System.in);
            double pi = 3.14;
            System.out.print("Masukkan nilai jari-jari lingkaran : ");
            int r = input.nextInt();
            try
            {
                if(r<=0)
                {
                throw new ArithmeticException();
                }
                double keliling = 2*pi*r;
                System.out.print("Keliling lingkaran adalah : ");
                System.out.println(keliling);
            }
            catch(ArithmeticException exception){
                System.err.printf("%nException: %s%n", exception);
                System.out.println("Nilai jari-jari tidak boleh nol atau negatif");
            }
     }
}