import java.util.concurrent.CountDownLatch;

public class Hei implements Runnable {
    int id;
    static CountDownLatch forste = new CountDownLatch(8);
    static CountDownLatch andre = new CountDownLatch(8);
    static CountDownLatch tredje = new CountDownLatch(8);
    
    Hei(int id) {
        this.id = id;
    } 

    public void run() {
        try {
            System.out.println("Hei 1 fra " + id);
            forste.countDown();
            forste.await();
            
            System.out.println("Hei 2 fra " + id);
            andre.countDown();
            andre.await();

            System.out.println("Hei 3 fra " + id);
            tredje.countDown();
        } catch(InterruptedException e) {
            System.exit(1);
        }
    }

    public static void main(String[] args) {
        for(int i = 0; i < 8; i++) {
            new Thread(new Hei(i)).start();
        }
        try {
            tredje.await();
        } catch(InterruptedException e) {
            System.exit(1);
        }
        System.out.println("Alle tradene har sagt hei tre ganger!");
    }
}