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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              /*

Queue.js

A function to represent a queue

Created by Kate Morley - http://code.iamkate.com/ - and released under the terms
of the CC0 1.0 Universal legal code:

http://creativecommons.org/publicdomain/zero/1.0/legalcode

*/

/* Creates a new queue. A queue is a first-in-first-out (FIFO) data structure -
 * items are added to the end of the queue and removed from the front.
 */
function Queue(){

  // initialise the queue and offset
  var queue  = [];
  var offset = 0;
  
  // Returns the the queue.
  this.get = function(){
    return queue;
  }
  
  // Returns the length of the queue.
  this.getLength = function(){
    return (queue.length - offset);
  }

  // Returns true if the queue is empty, and false otherwise.
  this.isEmpty = function(){
    return (queue.length == 0);
  }

  /* Enqueues the specified item. The parameter is:
   *
   * item - the item to enqueue
   */
  this.enqueue = function(item){
    queue.push(item);
  }

  /* Dequeues an item and returns it. If the queue is empty, the value
   * 'undefined' is returned.
   */
  this.dequeue = function(){

    // if the queue is empty, return immediately
    if (queue.length == 0) return undefined;

    // store the item at the front of the queue
    var item = queue[offset];

    // increment the offset and remove the free space if necessary
    if (++ offset * 2 >= queue.length){
      queue  = queue.slice(offset);
      offset = 0;
    }

    // return the dequeued item
    return item;

  }

  /* Returns the item at the front of the queue (without dequeuing it). If the
   * queue is empty then undefined is returned.
   */
  this.peek = function(){
    return (queue.length > 0 ? queue[offset] : undefined);
  }

}
// create a new queue
var queue = new Queue();

// enqueue an item
queue.enqueue('item1');
queue.enqueue('item2');
queue.enqueue('item3');
queue.enqueue('item4');
console.log(queue.getLength());
console.log(queue.get());
// dequeue an item
var item = queue.dequeue();
console.log(queue.getLength());
console.log(queue.get());

            
          
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