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Computer Science Introduction to Data Structures Building a Linked List Singly and Doubly Linked Lists

senay yakut
senay yakut
4,124 Points

can i have in javascript as well? thanks

can you show how i can implement singly and doubly linked list in javascript?

This course, and comment section, have been out for years, and yet there is still no JavaScript for this lesson. This is literally at the end of the JS Full Stack Tech Degree, and while the theoretical aspects of data structures are nice to learn in general, it would be ideal for students taking tracks other than Python to see this code implemented in the language they chose to study, and are paying to learn about. Looking at the comments here, it seems like students are being sent back and forth, trying to properly report this issue. This should have been handled a long time ago.

4 Answers

Of course, sometimes the community can help. Here's the JavaScript I built:

// Node for a Singly Linked List

class Node {
  /**
   * Object to store single node of a linked list
   * Contains data and link do next list
  */
  data;
  next_node;

  constructor( data ) {
        this.data = data;
    }
}

// Node for a Doubly Linked List

class LinkedNode {
  data;
  next_node;
  previous_node;

  constructor( data ) {
        this.data = data;
    }
}

/** Linked List
  * This works with both types of lists. Create a Node or LinkedNode as appropriate
*/

class LinkedList {
  head;

  is_empty() {
    return ( this.head === undefined );
  }

  size() {
    let current = this.head,
        count = 0;

    while ( current ) {
      count++;
      current = current.next_node;
    }

    return count;
  }
}

Greatly appreciate you sharing this!

It was noted at the top of these links to contact you guys for the copy of this lesson in another language we’re looking for. In my situation...Javascript. I did that, but they said that email address was no longer in service. So, they advised to post it here in the community, which seems odd since someone previously asked the same question here and they directed them back to that email address??....Would really appreciate the JS version of the links below......Many thanks

Singly and Doubly:

https://teamtreehouse.com/library/introduction-to-data-structures/building-a-linked-list/singly-and-doubly-linked-lists-2

Or…

This one, which covers singly, doubly with adding node, inserting nodes, search nodes, and delete nodes

https://teamtreehouse.com/library/introduction-to-data-structures/building-a-linked-list/linked-lists-operations

Steven Parker
Steven Parker
218,812 Points

If you find a bad link or email address on any pages you can report them as a bug to the Support staff. They're perhaps the folks who can help with your original issue too.

Matthew McQuain
Matthew McQuain
14,184 Points

As of 4.29.20, I got the exact same message from the Treehouse staff when I inquired about an earlier video in this same data structures series. I also requested something in JavaScript and was told to post here for help.

I'm genuinely surprised that there is very little content on Treehouse at all for Data Structures and Algorithms (in JavaScript). Not just here though, on YouTube as well. Trying to practice for whiteboard interviews in JavaScript is such a pain in the butt...

Steven Parker
Steven Parker
218,812 Points

You may have missed the note at the top of the page:

Note: If code is not provided below in the language you are looking for, send an email to content+cs@teamtreehouse.com

https://www.geeksforgeeks.org/implementation-linkedlist-javascript/ this was the best JavaScript implementation I've found so far. It's nice to take the code from there and bring it to JSFiddle/etc and play with it.