public class Blancanieves implements Runnable {

    Cocina c;

    public Blancanieves(Cocina c){
        this.c=c;
    }

    @Override
    public void run() {
        while (true){
            try {
                c.feed();
            }catch (InterruptedException e) {}
        }
    }

}

public class Enano implements Runnable {

    String name;
    Cocina c;

    public Enano(Cocina c,String name){
        this.c=c;
        this.name=name;
    }

    @Override
    public void run() {
        try {
            Thread.sleep((int)Math.random()*500);
            c.addWorker(this);
        } catch (InterruptedException e) {}
    }
    public String getName(){
        return name;
    }
}

public class Cocina {

    private static int maxSillas=4;

    private int sillas=maxSillas;

    public synchronized void addWorker(Enano e) throws InterruptedException {
        while (sillas==0) wait();
        sillas --;
        System.out.println(e.getName()+" "+sillas);
        notifyAll();
    }

    public synchronized void feed() throws InterruptedException{
        while (sillas==4) wait();
        sillas++;
        notifyAll();
    }

}