init. boilerplate for some structures

src/lib/LinkedList/ListNode.ts

@@ -0,0 +1,24 @@
+import Node from "../helpers/Node";
+
+export default class ListNode<T> extends Node<T> {
+    next: ListNode<T> | null
+    prev: ListNode<T> | null
+
+    constructor(data?: T, next?: ListNode<T>, prev?: ListNode<T>) {
+        super(data);
+        this.next = next || null;
+        this.prev = prev || null;
+    }
+
+    setNextNode(node: ListNode<T>) {
+        this.next = node;
+    }
+
+    get nextNode() {
+        return this.next;
+    }
+
+    get prevNode() {
+        return this.prev;
+    }
+}