@Override
public PriorityQueue<E> dequeue() {
if (this.length() == 0) {
head = null;
return EmptyLinkedList.getEmptyLinkedList();
}
head = (E) tail.head();
tail = tail.dequeue();
return new LinkedList<>(head, tail.copy());
}
public LinkedList(E head) {
this.head = head;
this.tail = EmptyLinkedList.getEmptyLinkedList();
}
public LinkedList() {
this.head = null;
this.tail = EmptyLinkedList.getEmptyLinkedList();
}