PriorityQueue::update

    (Available since version 1.0)

    PriorityQueue::update — Updates a node in the queue to a new priority

    Description

    public void PriorityQueue::update ( mixed $value , mixed $priority )

    Updates a node in the heap with the value, value, to a new priority, priority.

    If two nodes in the heap have the same value then only one will be changed.

    Parameters

    value

    The value to be updated.

    priority

    The new priority.

    Return Values

    No value is returned.

    Errors/Exceptions

    Throws SEIDS::Heaps::UpdateException when value1 is not in the heap.

    Examples

    Example #1 PriorityQueue::update example (using a pairing heap)

    <?php
    require 'vendor/autoload.php'; // A PSR-4 or PSR-0 autoloader
    use SEIDS\Heaps\Pairing\PriorityQueue;

    $q = new PriorityQueue();

    $q->insert('you',   9);
    $q->insert('never', 7);
    $q->insert('gonna', 5);
    $q->insert('give',  3);
    $q->insert('up',    1);

    $q2 = clone $q;

    $q->update('you', 2);

    foreach (    $q2 as $v) {
         var_dump($v);
    }

    echo     "\n";

    foreach (    $q as $v) {
         var_dump($v);
    }

    ?>

    The above example will output:

    string(3) "you"
string(5) "never"
string(5) "gonna"
string(4) "give"
string(2) "up"

string(5) "never"
string(5) "gonna"
string(4) "give"
string(3) "you"
string(2) "up"

    To Top