The SplDoublyLinkedList::prev() function is an inbuilt function in PHP which is used to move to the previous entry.
Syntax:
void SplDoublyLinkedList::prev( void )
Parameters: This function does not accepts any parameters.
Return Value: It does not return any value.
Below programs illustrate the SplDoublyLinkedList::prev() function in PHP:
Program 1:
<?php // Declare an empty SplDoublyLinkedList $list = new \SplDoublyLinkedList; // Use SplDoublyLinkedList::add() function to // add elements to the SplDoublyLinkedList $list ->add(0, 30); $list ->add(1, 20); $list ->add(2, 30); $list ->add(3, "Geeks" ); $list ->add(4, 'G' ); // Use SplDoublyLinkedList::prev() function // to move to previous entry $list ->prev(); // Display doubly linked list print_r( $list ); ?> |
SplDoublyLinkedList Object ( [flags:SplDoublyLinkedList:private] => 0 [dllist:SplDoublyLinkedList:private] => Array ( [0] => 30 [1] => 20 [2] => 30 [3] => Geeks [4] => G ) )
Program 2:
<?php // Declare an empty SplDoublyLinkedList $list = new \SplDoublyLinkedList(); // Use SplDoublyLinkedList::push() function to // add elements to the SplDoublyLinkedList $list ->push(1); $list ->push(2); $list ->push(3); $list ->push(8); $list ->push(5); // Use SplDoublyLinkedList::prev() function // to move to previous entry $list ->prev(); // Display doubly linked list var_dump( $list ); ?> |
object(SplDoublyLinkedList)#1 (2) { ["flags":"SplDoublyLinkedList":private]=> int(0) ["dllist":"SplDoublyLinkedList":private]=> array(5) { [0]=> int(1) [1]=> int(2) [2]=> int(3) [3]=> int(8) [4]=> int(5) } }
Reference: https://www.php.net/manual/en/spldoublylinkedlist.prev.php