- Write a program to Insertion Operation in Doubly Linked List?
<script>
var head;
class Node {
constructor(d) {
this.data = d;
this.next = null;
this.prev = null;
}
}
function push(new_data) {
var new_Node = new Node(new_data);
new_Node.next = head;
new_Node.prev = null;
if (head != null)
head.prev = new_Node;
head = new_Node;
}
function InsertBefore(next_node , new_data) {
if (next_node == null) {
document.write("The given next node can not be NULL");
return;
}
var new_node = new Node(new_data);
new_node.prev = next_node.prev;
next_node.prev = new_node;
new_node.next = next_node;
if (new_node.prev != null)
new_node.prev.next = new_node;
else
head = new_node;
}
function InsertAfter(prev_Node , new_data) {
if (prev_Node == null) {
document.write("The given previous node cannot be NULL ");
return;
}
var new_node = new Node(new_data);
new_node.next = prev_Node.next;
prev_Node.next = new_node;
new_node.prev = prev_Node;
if (new_node.next != null)
new_node.next.prev = new_node;
}
function append(new_data) {
var new_node = new Node(new_data);
var last = head;
new_node.next = null;
if (head == null) {
new_node.prev = null;
head = new_node;
return;
}
while (last.next != null)
last = last.next;
last.next = new_node;
new_node.prev = last;
}
function printlist(node) {
var last = null;
document.write("<br/>Traversal in forward Direction<br/>");
while (node != null) {
document.write(node.data + " ");
last = node;
node = node.next;
}
document.write();
document.write("<br/>Traversal in reverse direction<br/>");
while (last != null) {
document.write(last.data +"");
last = last.prev;
}
}
append(6);
push(7);
push(1);
append(4);
InsertAfter(head.next, 8);
InsertBefore(head.next.next, 5);
document.write("Created DLL is:<br/> ");
printlist(head);
</script>
