CS35 Queue ADT

#pragma once
/* Copyright (c) 2018
   Swarthmore College Computer Science Department, Swarthmore PA
   A. Danner, M. Gagne, J. Brody, Z. Palmer, A. Soni, L. Meeden
   Distributed as course material for Spring 2018
   CPSC 035: Data Structures and Algorithms
 */
 
/**
 * The Queue is a pure virtual (abstract) interface of a queue.  Queue
 * implementations should inherit from and implement this interface.
 * @tparam T The type of elements stored in the queue.
 */
template <typename T>
class Queue {
public:
    virtual ~Queue() { };

    /**
     * Adds an element to the queue.
     * @param item The element to enqueue.
     */
    virtual void enqueue(T element) = 0;

    /**
     * Removes an element from the queue.
     * @return The element that was dequeued.
     * @throws runtime_error If the queue was empty.
     */
    virtual T dequeue() = 0;

    /**
     * Determines the size of this queue.
     * @return The number of elements in the queue.
     */
    virtual int getSize() = 0;

    /**
     * Determines whether this queue is empty.
     * @return true if the queue is empty; false if it is not.
     */
    virtual bool isEmpty() = 0;

    /**
     * Retrieves the front element from the queue (without removing it).
     * @return The next element in the queue.
     * @throws runtime_error If the queue is empty.
     */
    virtual T getFront() = 0;

    // You can safely ignore the following code.  This eliminates some default
    // class routines, preventing you from using them accidentally.
    // Specifically, we are disabling the use of the copy constructor and the
    // copy assignment operator.  You can read more here:
    //   http://www.cplusplus.com/articles/y8hv0pDG/
public:
    Queue() { }
private:
    Queue(const Queue& other) = delete;
    Queue& operator=(const Queue& other) = delete;
};