int counter = 0;
Semaphore cmutex=1, klappe1=1, klappe2=1;

linke_FR() {
	cmutex.p();
	counter++;
	cmutex.v();

	klappe1.p();
	
	cmutex.p();
	counter--;
	cmutex.v();
}

rechte_FR() {
	
	klappe2.p();	

}

verpacken() {
	while(true) {
		cmutex.p();
		if(counter > 0)
			klappe1.v();
		else
			klappe2.v();
		cmutex.v();
	}
}