SplQueue::setIteratorMode
To have a good idea what you can do with SplHeap, I created a little example script that will show the rankings of Belgian soccer teams in the Jupiler League.
<?php
/**
* A class that extends SplHeap for showing rankings in the Belgian
* soccer tournament JupilerLeague
*/
class JupilerLeague extends SplHeap
{
/**
* We modify the abstract method compare so we can sort our
* rankings using the values of a given array
*/
public function compare($array1, $array2)
{
$values1 = array_values($array1);
$values2 = array_values($array2);
if ($values1[0] === $values2[0]) return 0;
return $values1[0] < $values2[0] ? -1 : 1;
}
}
// Let's populate our heap here (data of 2009)
$heap = new JupilerLeague();
$heap->insert(array ('AA Gent' => 15));
$heap->insert(array ('Anderlecht' => 20));
$heap->insert(array ('Cercle Brugge' => 11));
$heap->insert(array ('Charleroi' => 12));
$heap->insert(array ('Club Brugge' => 21));
$heap->insert(array ('G. Beerschot' => 15));
$heap->insert(array ('Kortrijk' => 10));
$heap->insert(array ('KV Mechelen' => 18));
$heap->insert(array ('Lokeren' => 10));
$heap->insert(array ('Moeskroen' => 7));
$heap->insert(array ('Racing Genk' => 11));
$heap->insert(array ('Roeselare' => 6));
$heap->insert(array ('Standard' => 20));
$heap->insert(array ('STVV' => 17));
$heap->insert(array ('Westerlo' => 10));
$heap->insert(array ('Zulte Waregem' => 15));
// For displaying the ranking we move up to the first node
$heap->top();
// Then we iterate through each node for displaying the result
while ($heap->valid()) {
list ($team, $score) = each ($heap->current());
echo $team . ': ' . $score . PHP_EOL;
$heap->next();
}
?>
This results in the following output:
Club Brugge: 21
Anderlecht: 20
Standard: 20
KV Mechelen: 18
STVV: 17
Zulte Waregem: 15
AA Gent: 15
G. Beerschot: 15
Charleroi: 12
Racing Genk: 11
Cercle Brugge: 11
Kortrijk: 10
Lokeren: 10
Westerlo: 10
Moeskroen: 7
Roeselare: 6
Hope this example paved the way for more complex implementations of SplHeap.
The SplHeap class
소개
The SplHeap class provides the main functionalities of an Heap.
클래스 개요
Table of Contents
- SplHeap::compare — Compare elements in order to place them correctly in the heap while sifting up.
- SplHeap::__construct — Constructs a new empty heap
- SplHeap::count — Counts the number of elements in the heap.
- SplHeap::current — Return current node pointed by the iterator
- SplHeap::extract — Extracts a node from top of the heap and sift up.
- SplHeap::insert — Inserts an element in the heap by sifting it up.
- SplHeap::isEmpty — Checks whether the heap is empty.
- SplHeap::key — Return current node index
- SplHeap::next — Move to the next node
- SplHeap::recoverFromCorruption — Recover from the corrupted state and allow further actions on the heap.
- SplHeap::rewind — Rewind iterator back to the start (no-op)
- SplHeap::top — Peaks at the node from the top of the heap
- SplHeap::valid — Check whether the heap contains more nodes
add a note
User Contributed NotesSplHeap
Michelangelo van Dam
07-Oct-2009 06:44
07-Oct-2009 06:44