PrimeNumber

gistfile1.txt

import java.util.Scanner;

/**
 * Created by this busta (Luke) on 4/18/2015.
 */

public class PrimeNumberRecursive {
    
    public static void main(String[] args) {
        
        Scanner console = new Scanner(System.in);
        
        while (true) {
            System.out.print("Enter a prime number (enter 0 to exit): ");
            int test = console.nextInt();
            if (test == 0) {
                break;
            }
            
            boolean prime = isPrime(test, 2);
            System.out.print(test + " is ");
            if (!prime) System.out.print("not ");
            System.out.println("a prime number");
        }
    }
    
    public static boolean isPrime(int n, int d) {
        if (d < n) {
            if (n % d == 0) return false;
            return isPrime(n, d+1);
        } else {
            return true;
        }
    }
}