Delete A Node In A Doubly Linked List (JS)

Hello Coders! Welcome to nkcoderz website. In this post, you will learn how to delete a node in a doubly linked list js, code for the above task given below:

How To Delete A Node In A Doubly Linked List (JS)

class Node
{
    constructor(val)
     {
            this.data = val;
            this.prev = null;
            this.next = null;
     }
}
var head = null;
function insertlast(val)
{
      var last = new Node(val);
      if(head == null)
      {
          last.prev = null;
          last.next = null;
          head = last;
      }
      else
      {
          var temp = head;
          while(temp.next != null)
          {
             temp = temp.next;
          }

          temp.next = last;
          last.prev = temp;
          last.next = null;
      }
}
function del(key)
{
     if(head == null)
          return;

      var temp = head;
      while(temp != null && temp.data != key)
      {
          temp = temp.next;
      }
      if(temp == null)
          document.write("Key Not Found");
      else if(temp == head)
      {
          head = head.next;
          head.prev = null;
      }
      else if(temp.next == null)
          temp.prev.next = null;
      else
      {
          temp.prev.next = temp.next;
          temp.next.prev = temp.prev;
      }
}
function print()
{
      var temp = head;
      var last = null;
      while(temp != null)
      {
          document.write(temp.data);
          if(temp.next == null)
              last = temp;
          temp = temp.next;
      }
}
insertlast(5);
insertlast(10);
insertlast(15);
print();
document.write("After deleting:")
del(10);
print();

In the above code we have:

Output:

5
10
15
After deleting:
5
15