PHP Ds\Queue isEmpty() Function

The Ds\Queue::isEmpty() Function in PHP is used to whether a particular Queue instance is empty or not. It returns True if the Queue is empty otherwise it returns False.

Syntax:

bool public Ds\Queue::isEmpty ( void )

Parameters: This function does not accepts any parameters.

Return Value: This function returns a boolean value based on whether this Queue is empty or not. It returns True if the Queue is empty otherwise it returns False.

Below programs illustrate the Ds\Queue::isEmpty() Function in PHP:

Program 1:

<?php

// Declare new Queue
$q = new \Ds\Queue();

// Initially Queue is Empty
var_dump($q->isEmpty());

// Add elements to the Queue
$q->push("One");
$q->push("Two");
$q->push("Three");

// Check again if the Queue
// is Empty
var_dump($q->isEmpty());

?>

Output:

bool(true)
bool(false)

Program 2:

<?php

// Declare new Queue
$q = new \Ds\Queue();

// Initially Queue is Empty
var_dump($q->isEmpty());

// Add elements to the Queue
$q->push("Geeks");
$q->push("for");
$q->push("Geeks");

// Check again if the Queue
// is Empty
var_dump($q->isEmpty());

?>

Output:

bool(true)
bool(false)

Reference: http://php.net/manual/en/ds-priorityqueue.isempty.php