Add solution #206

Author: JoshCrozier

README.md

@@ -47,6 +47,7 @@
 151|[Reverse Words in a String](./0151-reverse-words-in-a-string.js)|Medium|
 152|[Maximum Product Subarray](./0152-maximum-product-subarray.js)|Medium|
 203|[Remove Linked List Elements](./0203-remove-linked-list-elements.js)|Easy|
+206|[Reverse Linked List](./0206-reverse-linked-list.js)|Easy|
 217|[Contains Duplicate](./0217-contains-duplicate.js)|Easy|
 219|[Contains Duplicate II](./0219-contains-duplicate-ii.js)|Easy|
 226|[Invert Binary Tree](./0226-invert-binary-tree.js)|Easy|

solutions/0206-reverse-linked-list.js

@@ -0,0 +1,32 @@
+/**
+ * 206. Reverse Linked List
+ * https://leetcode.com/problems/reverse-linked-list/
+ * Difficulty: Easy
+ *
+ * Given the head of a singly linked list, reverse the list, and return the reversed list.
+ */
+
+/**
+ * Definition for singly-linked list.
+ * function ListNode(val, next) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.next = (next===undefined ? null : next)
+ * }
+ */
+/**
+ * @param {ListNode} head
+ * @return {ListNode}
+ */
+var reverseList = function(head) {
+  let prev = null;
+  let tail = head;
+
+  while (tail) {
+    const next = tail.next;
+    tail.next = prev;
+    prev = tail;
+    tail = next;
+  }
+
+  return prev;
+};