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author | Mario Vavti <mario@mariovavti.com> | 2017-05-31 09:56:35 +0200 |
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committer | Mario Vavti <mario@mariovavti.com> | 2017-05-31 09:56:35 +0200 |
commit | 47d55694a4c84b6c12c0db61a69bcac8b671b20e (patch) | |
tree | b15e96f4ea67e2214a66a9d28dafaf53d25b98ec /library/HTMLPurifier/Queue.php | |
parent | 087f9784e3c5a860ed2b86e7f9e8e9f312038546 (diff) | |
parent | f0e615dee529e031663576286345141ad2996974 (diff) | |
download | volse-hubzilla-2.4.tar.gz volse-hubzilla-2.4.tar.bz2 volse-hubzilla-2.4.zip |
Merge branch '2.4RC'2.4
Diffstat (limited to 'library/HTMLPurifier/Queue.php')
-rw-r--r-- | library/HTMLPurifier/Queue.php | 56 |
1 files changed, 0 insertions, 56 deletions
diff --git a/library/HTMLPurifier/Queue.php b/library/HTMLPurifier/Queue.php deleted file mode 100644 index f58db9042..000000000 --- a/library/HTMLPurifier/Queue.php +++ /dev/null @@ -1,56 +0,0 @@ -<?php - -/** - * A simple array-backed queue, based off of the classic Okasaki - * persistent amortized queue. The basic idea is to maintain two - * stacks: an input stack and an output stack. When the output - * stack runs out, reverse the input stack and use it as the output - * stack. - * - * We don't use the SPL implementation because it's only supported - * on PHP 5.3 and later. - * - * Exercise: Prove that push/pop on this queue take amortized O(1) time. - * - * Exercise: Extend this queue to be a deque, while preserving amortized - * O(1) time. Some care must be taken on rebalancing to avoid quadratic - * behaviour caused by repeatedly shuffling data from the input stack - * to the output stack and back. - */ -class HTMLPurifier_Queue { - private $input; - private $output; - - public function __construct($input = array()) { - $this->input = $input; - $this->output = array(); - } - - /** - * Shifts an element off the front of the queue. - */ - public function shift() { - if (empty($this->output)) { - $this->output = array_reverse($this->input); - $this->input = array(); - } - if (empty($this->output)) { - return NULL; - } - return array_pop($this->output); - } - - /** - * Pushes an element onto the front of the queue. - */ - public function push($x) { - array_push($this->input, $x); - } - - /** - * Checks if it's empty. - */ - public function isEmpty() { - return empty($this->input) && empty($this->output); - } -} |