import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import java.util.concurrent.locks.Condition;
import java.util.*;


class Bord{

  private ArrayList<String> bord = new ArrayList<>();
  private Lock bordLaas = new ReentrantLock();
  private Condition ingenKaffe = bordLaas.newCondition();
  private int antallFerdige = 0;
  private int antallBarista;

  public Bord(int antallBarista){
    this.antallBarista = antallBarista;
  }

  public void server(String kaffe){
    bordLaas.lock();
    if(kaffe.equals("tomt")){
      antallFerdige++;
    }else{
      bord.add(kaffe);
    }
    ingenKaffe.signalAll();
    bordLaas.unlock();
  }

  public String hentKaffe(){
    bordLaas.lock();
    try{
      while(bord.isEmpty()){
        if(antallBarista == antallFerdige){
          ingenKaffe.signalAll();
          return "tomt";
        }
        ingenKaffe.await();
      }
      return bord.remove(0);
    } catch (InterruptedException e){
      System.out.println("Ble forstyrret naar kaffe skulle hentes");
    } finally {
      bordLaas.unlock();
    }
    return "tomt";
  }
}