The SplDoublyLinkedList::offsetUnset() function is an inbuilt function in PHP which is used to unset the value at given index.
Syntax:
php
php
void SplDoublyLinkedList::offsetUnset( $index )Parameters: This function accepts a single parameter $index which holds the index value whose value to be unset. Return Value: It does not return any value. Below programs illustrate the SplDoublyLinkedList::offsetUnset() 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');
$list->rewind();
// Use SplDoublyLinkedList::offsetUnset() function
// to unset the value at given index
$list->offsetUnset(0);
$list->offsetUnset(1);
$list->offsetUnset(0);
$list->offsetUnset(1);
var_dump($list);
?>
Output:
Program 2:
object(SplDoublyLinkedList)#1 (2) {
["flags":"SplDoublyLinkedList":private]=>
int(0)
["dllist":"SplDoublyLinkedList":private]=>
array(1) {
[0]=>
string(5) "Geeks"
}
}
<?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::offsetUnset() function
// to unset the value at given index
$list->offsetUnset(1);
$list->offsetUnset(2);
print_r($list);
?>
Output:
Reference: https://www.php.net/manual/en/spldoublylinkedlist.offsetunset.php
SplDoublyLinkedList Object
(
[flags:SplDoublyLinkedList:private] => 0
[dllist:SplDoublyLinkedList:private] => Array
(
[0] => 1
[1] => 3
[2] => 5
)
)