The SplDoublyLinkedList::__construct() function is an inbuilt function in PHP which is used to create a new empty doubly linked list.
Syntax:
public SplDoublyLinkedList::__construct( void )
Parameters: This function does not accept any parameter.
Return Value: This function does not return any value.
Below programs illustrate the SplDoublyLinkedList::__construct() function in PHP:
Program 1:
<?php // Declare an empty SplDoublyLinkedList $list = new SplDoublyLinkedList();
// Push the element into SplDoublyLinkedList $list ->push(10);
$list ->push(20);
$list ->push(30);
// Display the SplDoublyLinkedList var_dump( $list );
?> |
Output:
object(SplDoublyLinkedList)#1 (2) { ["flags":"SplDoublyLinkedList":private]=> int(0) ["dllist":"SplDoublyLinkedList":private]=> array(3) { [0]=> int(10) [1]=> int(20) [2]=> int(30) } }
Program 2:
<?php // Declare an empty SplDoublyLinkedList $list = new SplDoublyLinkedList();
// Add the element into SplDoublyLinkedList $list ->add(0, "Welcome" );
$list ->add(1, "to" );
$list ->add(2, "GeeksforGeeks" );
$list ->add(3, "A" );
$list ->add(4, "Computer" );
$list ->add(5, "Science" );
$list ->add(6, "Portal" );
// Display the SplDoublyLinkedList var_dump( $list );
?> |
Output:
object(SplDoublyLinkedList)#1 (2) { ["flags":"SplDoublyLinkedList":private]=> int(0) ["dllist":"SplDoublyLinkedList":private]=> array(7) { [0]=> string(7) "Welcome" [1]=> string(2) "to" [2]=> string(13) "GeeksforGeeks" [3]=> string(1) "A" [4]=> string(8) "Computer" [5]=> string(7) "Science" [6]=> string(6) "Portal" } }