How To Use an Array as a Queue in PHP?

A queue is a simple data structure that manages data elements following the first-in-first-out rule. You use the following two functions together to use an array as a queue:

• array_push($array, $value) - Pushes a new value to the end of an array. The value will be added with an integer key like $array[]=$value.
• array_shift($array) - Remove the first value from the array and returns it. All integer keys will be reset sequentially starting from 0.

Here is a PHP script on how to use an array as a queue:

<?php
$waitingList = array();
array_push($waitingList, "Joe");
array_push($waitingList, "Leo");
array_push($waitingList, "Kim");
$next = array_shift($waitingList);
array_push($waitingList, "Kia");
$next = array_shift($waitingList);
array_push($waitingList, "Sam");
print("Current waiting list:\n");
print_r($waitingList);
?>

This script will print:

Current waiting list:
Array
(
    [0] => Kim
    [1] => Kia
    [2] => Sam
)

⇒ Using an Array as a Stack in PHP

⇐ Merging Two Arrays into a Single Array in PHP

⇑ PHP Built-in Functions for Arrays

⇑⇑ PHP Tutorials