PHP implements the Queue Data Structure

A Queue is a special first-in-first-out linear table that can only be deleted at the front end (usually called a Queue) and inserted at the backend (usually called a Queue ). The end of the delete operation is called the head of the team, and the end of the insert operation is called the end of the team. A queue organizes data according to the principle of first-in-first-out or second-out. When no elements exist in the queue,

A Queue is a special first-in-first-out linear table that can only be deleted at the front end (usually called a Queue) and inserted at the backend (usually called a Queue ). The end of the delete operation is called the head of the team, and the end of the insert operation is called the end of the team. A queue organizes data according to the principle of first-in-first-out or second-out. When no elements exist in the queue,

A Queue is a special first-in-first-out linear table that can only be deleted at the front end (usually called a Queue) and inserted at the backend (usually called a Queue ). The end of the delete operation is called the head of the team, and the end of the insert operation is called the end of the team. A queue organizes data according to the principle of first-in-first-out or second-out. When there are no elements in the queue, it is called an empty queue.

Data Structure and algorithm (implemented in PHP)-Queue)

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/** * Data structures and algorithms (implemented in PHP)-Queue ). * * @ Author creative programming (TOPPHP. ORG) * @ Copyright Copyright (c) 2013 creative programming (TOPPHP. ORG) All Rights Reserved * @license http://www.opensource.org/licenses/mit-license.php MIT LICENSE * @version 1.0.0 - Build20130607 */ class Queue { /** * Queue. * * @var array */ private$queue; /** * Queue length. * * @var integer */ private$size; /** * Constructor-Initialize data. */ publicfunction __construct() { $this->queue =array(); $this->size = 0; } /** * Queue operations. * * @ Param mixed $ data queue data. * @ Return object returns the object itself. */ publicfunction enqueue($data) { $this->queue[$this->size++] =$data; return$this; } /** * Team-out operations. * * @ Return mixed: FALSE is returned when the queue is empty. Otherwise, the Header element of the queue is returned. */ publicfunction dequeue() { if(!$this->isEmpty()) { --$this->size; $front= array_splice($this->queue, 0, 1); return$front[0]; } returnFALSE; } /** * Get the queue. * * @ Return array returns the entire queue. */ publicfunction getQueue() { return$this->queue; } /** * Obtain the element of the team header. * * @ Return mixed: FALSE is returned when the queue is empty. Otherwise, the Header element of the queue is returned. */ publicfunction getFront() { if(!$this->isEmpty()) { return$this->queue[0]; } returnFALSE; } /** * Get the queue length. * * @ Return integer returns the length of the queue. */ publicfunction getSize() { return$this->size; } /** * Check whether the queue is empty. * * @ Return boolean if the queue is empty, TRUE is returned; otherwise, FALSE is returned. */ publicfunction isEmpty() { return0 === $this->size; } } ?>

Sample Code

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$queue = new Queue(); $queue->enqueue(1)->enqueue(2)->enqueue(3)->enqueue(4)->enqueue(5)->enqueue(6); echo ' ', print_r($queue->getQueue(), TRUE),' '; $queue->dequeue(); echo ' ', print_r($queue->getQueue(), TRUE),' '; ?>

Note: PHP array functions such as queue functions exist: array_unshift (queuing) and array_shift (queuing ).