/**
     * Locates person in this house.
     *
     * @param person Person of interest
     * @return room where the person is located,
     *         null if the person is not in the house
     */
    public Room whereIs(Person person){
        for(Room r : personMap.keySet()){
            List<Person> p = new ArrayList<Person>();
            p.addAll(personMap.get(r));

            if(p.contains(person)){
                return r ;
                }

            p.clear();
        }
        return null; //p malo by byt null, ak nie je, vrati sa true, co je v cykle.

    }