package wek3;
    /**
     * QueueADT defines the interface to a queue collection.
     *
     * @author Lewis and Chase
     * @version 4.0
     */
    public interface QueueADT<T>
    {
        public void enqueue(T element);
        public T dequeue();
        public T first();
        public boolean isEmpty();
        public int size();
        @Override
        public String toString();
    }