import java.util.ArrayList;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

//Standard regle for laaser:
// Lock laas = new ReentrantLock();
// laas.lock();
// try{
//  KODE
// }
// finally{
// laas.unlock();
// }

//Monitor
//Kritisk omraade!!!
class NavnRegister{

  private Lock laas = new ReentrantLock();

  private ArrayList<String> navnListe = new ArrayList<String>();


  public void settInn(String n){
    laas.lock();
    try{
      navnListe.add(n);
    }
    finally{
      laas.unlock();
    }
  }

  public String taUt(int p){
    laas.lock();
    try{
      return navnListe.remove(p);
    }
    finally{
      laas.unlock();
    }
  }

  public String hent(int p){
    laas.lock();
    try{
      return navnListe.get(p);
    }
    finally{
      laas.unlock();
    }
  }

}