Heap::update

    (Available since version 1.0)

    Heap::update — Updates a node in the heap to a new value

    Description

    public void Heap::update ( mixed $value1 , mixed $value2 )

    Updates a node in the heap from its current value to a new value, value2. Where the current value is given by executing Heap::value() on value1.

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

    Note:

    Runs in Θ(log(n)), where n is the size of the heap.

    Parameters

    value1

    The current value.

    value2

    The new value.

    Return Values

    No value is returned.

    Errors/Exceptions

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

    Examples

    Example #1 Heap::update example (using a max-heap)

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

    $mh = new MaxHeap();

    $mh->insert(1);
    $mh->insert(2);
    $mh->insert(3);
    $mh->insert(4);
    $mh->insert(5);

    $mh2 = clone $mh;

    $mh->update(2, 6);
    $mh->update(4, 0);

    foreach (    $mh2 as $v) {
         var_dump($v);
    }

    echo     "\n";

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

    ?>

    The above example will output:

    int(5)
int(4)
int(3)
int(2)
int(1)

int(6)
int(5)
int(3)
int(1)
int(0)

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