The SplDoublyLinkedList::isEmpty() function is an inbuilt function in PHP which is used to check whether the doubly linked list is empty or not.
Syntax:
bool SplDoublyLinkedList::isEmpty( void )
Parameters: This function does not accepts any parameters.
Return Value: This function returns True if doubly linked list is empty, False otherwise.
Below programs illustrate the SplDoublyLinkedList::isEmpty() function in PHP:
Program 1:
<?php // Declare an empty SplDoublyLinkedList $list = new \SplDoublyLinkedList; // Use isEmpty function $res = $list ->isEmpty(); var_dump( $res ); // 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 isEmpty function $res = $list ->isEmpty(); var_dump( $res ); ?> |
bool(true) bool(false)
Program 2:
<?php // Declare an empty SplDoublyLinkedList $list = new \SplDoublyLinkedList; // Use isEmpty function $res = $list ->isEmpty(); var_dump( $res ); // 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 isEmpty function $res = $list ->isEmpty(); var_dump( $res ); ?> |
bool(true) bool(false)
Reference: https://www.php.net/manual/en/spldoublylinkedlist.isempty.php