SPLStack & SplQueue

splqueue.php

<?php
 
$doublyList = new SplQueue();
 
if ($doublyList->isEmpty()) {
	$doublyList->enqueue('PHP');
	$doublyList->enqueue('Java');
	$doublyList->enqueue('Python');
	$doublyList->enqueue('Ruby');
}
 
print_r($doublyList);
 
if (! $doublyList->offsetExists(4)) {
	$doublyList->enqueue('JS');
}
 
print_r($doublyList);
 
// dequeue
$doublyList->dequeue();
print_r($doublyList);

/** output:
SplQueue Object
(
    [flags:SplDoublyLinkedList:private] => 4
    [dllist:SplDoublyLinkedList:private] => Array
        (
            [0] => PHP
            [1] => Java
            [2] => Python
            [3] => Ruby
        )

)


SplQueue Object
(
    [flags:SplDoublyLinkedList:private] => 4
    [dllist:SplDoublyLinkedList:private] => Array
        (
            [0] => PHP
            [1] => Java
            [2] => Python
            [3] => Ruby
            [4] => JS
        )

)


SplQueue Object
(
    [flags:SplDoublyLinkedList:private] => 4
    [dllist:SplDoublyLinkedList:private] => Array
        (
            [0] => Java
            [1] => Python
            [2] => Ruby
            [3] => JS
        )

)
**/

splstack.php

<?php
 
$stack = new SPLStack();
 
$stack->push('a');
$stack->push('b');
$stack->push('c');
$stack->push('d');
 
echo $stack->pop();
echo $stack->pop();
 
// output: dc