$pointer->next->next = $pointer->next->next->next;
} else {
$pointer->next->next = null;
}
}
public function insert_after($value, $node_value)
{
$pointer = $this->head;
$newNode = new Node($value);
while ($pointer->value != $node_value) {
$pointer = $pointer->next;
}
$newNode->prev = $pointer;
$newNode->next = $pointer->next;
$pointer->next->prev = $newNode;
$pointer->next = $newNode;
}
public function displayAll()
{
var_dump($this->head);
var_dump($this->head->next);
return $this;
}
}
$list = new DoublyLinkedList();
$list->add_node(1);
$list->add_node(2);
$list->add_node(3);
$list->delete_node(2);
$list->insert_after(2, 1);
var_dump($list);
$node = $this->head;
//have $node point to where $this->head is pointing to
if ($node == NULL) {
//if $node points to NULL
echo "Linked List is empty";
return NULL;
}
$current = $current->next;
while ($node->next != NULL) {
echo "Node value is " . $node->value . "<br />";
$node = $node->next;
//now have $node point to where $node->next is pointing to
}
echo "Node value is " . $node->value . "<br />";
//have it print the last node value
}
}
$dll = new DoublyLinkedList();
//creates a new instance of the doubly linked list
$dll->add(5);
//should add a new node with the value of 5
$dll->add(7);
//should add a new node with the value of 7
$dll->add(10);
var_dump($dll);
// $dll->removeAllNodesWithValueOf(7); //should remove all nodes with value of 7
// $dll->remove(1); //removes node of position 1
// $dll->add(3); //should add a new node with the value of 3
// $dll->insert(1, 100); //insert a new node of value 100 in the position 1
$dll->printValues();
//should print all the values in the doubly linked list
$this->{$head}->next->prev = $node;
} else {
if ($node->next == null) {
$node->prev->next = null;
} else {
$node->prev->next = $node->next;
$node->next->prev = $node->prev;
}
}
}
public function displayAll()
{
var_dump($this->head);
var_dump($this->head->next);
return $this;
}
}
$list = new DoublyLinkedList();
$list->insert_Beginning(1);
$list->insert_Beginning(2);
$list->insert_Beginning(3);
$list->insert_Before(4, 2);
//$list->insert_End($list->head,3);
var_dump($list);
//$list->insert_After(2,1);
//$list->insert_After(3,2);
//$list->insert_End()
// $list->add_node(2);
//$list->add_node(3);
//$list->add_node(4);
//$list->displayAll();
public function testPushFrontList()
{
$l = new DoublyLinkedList();
$e1 = $l->pushFront(1);
$e2 = $l->pushBack(2);
$e3 = $l->pushBack(3);
$other = new DoublyLinkedList();
$e4 = $other->pushBack(4);
$e5 = $other->pushBack(5);
$l->pushFrontList($other);
$this->assertEquals(5, $l->len());
$this->assertEquals(4, $l->getFront()->getValue());
$this->assertEquals(5, $l->getFront()->getNext()->getValue());
$this->assertEquals($e1, $l->getFront()->getNext()->getnext());
// pushFrontList the same list will double its elements.
$other->pushFrontList($other);
$this->assertEquals(4, $other->len());
$this->assertEquals(4, $other->getFront()->getValue());
$this->assertEquals(5, $other->getFront()->getNext()->getValue());
$this->assertEquals(4, $other->getFront()->getNext()->getNext()->getValue());
// pushFrontList empty list won't alter the list.
$emptyList = new DoublyLinkedList();
$other->pushFrontList($emptyList);
$this->assertEquals(4, $other->len());
}
//have $node point to where $this->head is pointing to
if ($node == NULL) {
//if $node points to NULL
echo "Linked List is empty";
return NULL;
}
while ($node->next != NULL) {
echo "Node value is " . $node->value . "<br />";
$node = $node->next;
//now have $node point to where $node->next is pointing to
}
echo "Node value is " . $node->value . "<br />";
//have it print the last node value
}
}
$dll = new DoublyLinkedList();
//creates a new instance of the doubly linked list
$dll->add(5);
//should add a new node with the value of 5
$dll->add(7);
//should add a new node with the value of 7
$dll->add(10);
$dll->removeAllNodesWithValueOf(7);
//should remove all nodes with value of 7
$dll->remove(1);
//removes node of position 1
$dll->add(3);
//should add a new node with the value of 3
$dll->insert(1, 100);
//insert a new node of value 100 in the position 1
$dll->printValues();
$current->prev->next = $current->next;
$current->next->prev = $current->prev;
$current->prev = NULL;
$current->next = NULL;
$current->value = NULL;
}
}
return $this;
}
function insertNode($value, $insertion_point)
{
$current = $this->head;
while ($current->value !== $insertion_point) {
$current = $current->next;
}
if ($current === $this->tail) {
$this->addNode($value);
} else {
$insert = new Node($value);
$insert->next = $current->next;
$current->next = $insert;
$insert->prev = $current;
$insert->next->prev = $insert;
return $this;
}
}
}
$list = new DoublyLinkedList(1);
$list->addNode(2)->addNode(3)->insertNode(4, 3);
$list->deleteNode(6);
var_dump($list);
/**
* Inserts a copy of an other list at the front of list.
*
* Other list and current list may be the same.
*
* @param DoublyLinkedList $other Other list to insert
*
* @api
*/
public function pushFrontList(DoublyLinkedList $other)
{
for ($i = $other->len(), $el = $other->getBack(); $i > 0; $i--, $el = $el->getPrev()) {
$this->insertValue($el->getValue(), $this->root);
}
}
