The SplPriorityQueue class

Introduction

The SplPriorityQueue class provides the main functionalities of a prioritized queue, implemented using a max heap.

Note: The order of elements with identical priority is undefined. It may differ from the order in which they have been inserted.

SplPriorityQueue

implements Iterator Countable

/* Constants */

public const int SplPriorityQueue::EXTR_BOTH;

public const int SplPriorityQueue::EXTR_PRIORITY;

public const int SplPriorityQueue::EXTR_DATA;

/* Methods */

public int compare(mixed $priority1, mixed $priority2)

public int count()

public mixed current()

public mixed extract()

public int getExtractFlags()

public true insert(mixed $value, mixed $priority)

public bool isCorrupted()

public bool isEmpty()

public int key()

public void next()

public true recoverFromCorruption()

public void rewind()

public int setExtractFlags(int $flags)

public mixed top()

public bool valid()

Table of Contents

SplPriorityQueue::compare — Compare priorities in order to place elements correctly in the heap while sifting up
SplPriorityQueue::count — Counts the number of elements in the queue
SplPriorityQueue::current — Return current node pointed by the iterator
SplPriorityQueue::extract — Extracts a node from top of the heap and sift up
SplPriorityQueue::getExtractFlags — Get the flags of extraction
SplPriorityQueue::insert — Inserts an element in the queue by sifting it up
SplPriorityQueue::isCorrupted — Tells if the priority queue is in a corrupted state
SplPriorityQueue::isEmpty — Checks whether the queue is empty
SplPriorityQueue::key — Return current node index
SplPriorityQueue::next — Move to the next node
SplPriorityQueue::recoverFromCorruption — Recover from the corrupted state and allow further actions on the queue
SplPriorityQueue::rewind — Rewind iterator back to the start (no-op)
SplPriorityQueue::setExtractFlags — Sets the mode of extraction
SplPriorityQueue::top — Peeks at the node from the top of the queue
SplPriorityQueue::valid — Check whether the queue contains more nodes