PHP | Ds\Deque allocate() Function

The Ds\Deque::allocate() function is an inbuilt function in PHP which is used to allocate memory as specified in the argument. If the argument is not defined, then the Deque of default size will be created.

Syntax:

public Ds\Deque::allocate( $capacity ) : void

Parameters: This function accepts single parameter $capacity which holds the number of values for which space is to be allocated.

Return Value: This function does not return any value.

Below programs illustrate the Ds\Deque::allocate() function in PHP:

Program 1:

<?php

// Declare Deque of default size
$deq = new \Ds\Deque();

// Display the capacity of Deque
var_dump($deq->capacity());


// Allocating space for 50 values
// to the Deque
$deq->allocate(50);

// Display the capacity of Deque
var_dump($deq->capacity());

?>

Output:

int(8)
int(64)

Program 2:

<?php

// Declare Deque of default size
$deck = new \Ds\Deque();

// Display the Deque capacity
var_dump($deck->capacity());

// Allocating space for 50 values
// to the Deque
$deck->allocate(50);

// Display the Deque capacity
var_dump($deck->capacity());

// Allocating space for 60 values
// to the Deque
$deck->allocate(60);

// Display the Deque capacity
var_dump($deck->capacity());

?>

Output:

int(8)
int(64)
int(64)

Reference: http://php.net/manual/en/ds-deque.allocate.php