public class Teller {
	private int teller=0;
	public synchronized void verwerkTienTallen() throws InterruptedException {
		while (teller<10)
			wait();
		teller-=10;
		System.out.println("teller is verlaagd en is nu "+teller);		
	}
	public synchronized void verhoog(int n) {
		teller+=n;
		notify();
	}
}