Data Structures: Reverse a Doubly Linked List

Data Structures/doublyLinkedListReverse.js

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+// https://www.freecodecamp.org/learn/coding-interview-prep/data-structures/reverse-a-doubly-linked-list
+
+var Node = function (data, prev) {
+  this.data = data;
+  this.prev = prev;
+  this.next = null;
+};
+var DoublyLinkedList = function () {
+  this.head = null;
+  this.tail = null;
+  // Only change code below this line
+  this.reverse = () => {
+    const newTail = this.head;
+    let node = this.head;
+    while (node !== null) {
+      const newPrev = node.next;
+      node.next = node.prev;
+      node.prev = newPrev;
+      node = newPrev;
+    }
+    this.head = this.tail;
+    this.tail = newTail;
+  };
+  // Only change code above this line
+};