86

swolecoder · swolecoder · commit 7b4952d82a77 · 2021-01-01T23:28:51.000-05:00
diff --git a/Day86/index.js b/Day86/index.js
@@ -0,0 +1,41 @@
+/**
+ * // Definition for a Node.
+ * function Node(val, left, right) {
+ *      this.val = val;
+ *      this.left = left;
+ *      this.right = right;
+ *  };
+ */
+
+/**
+ * @param {Node} root
+ * @return {Node}
+ */
+var treeToDoublyList = function (root) {
+
+    if (!root) return null;
+    let head = null;
+    let prev = null;
+
+    function inOrder(node) {
+        if (!node) return null;
+        inOrder(node.left);
+
+        //do stuff
+        if (prev == null) {
+            prev = node
+            head = node
+        } else {
+            node.left = prev;
+            prev.right = node;
+            prev = node
+        }
+
+        inOrder(node.right)
+    }
+    inOrder(root);
+
+    head.left = prev;
+    prev.right = head;
+    return head
+};
diff --git a/README.md b/README.md
@@ -190,4 +190,6 @@ If you are loving solving problems in leetcode, please contact me to enjoy it to
 
 |Day 84| [1640. Check Array Formation Through Concatenation](https://leetcode.com/problems/check-array-formation-through-concatenation/) | [javascript]()|[:memo:](https://leetcode.com/problems/check-array-formation-through-concatenation/)|Easy|
 
-|Day 85| [1640. Check Array Formation Through Concatenation](https://leetcode.com/problems/palindrome-permutation/) | [javascript]()|[:memo:](https://leetcode.com/problems/palindrome-permutation/)|Easy|
+|Day 85| [1640. Check Array Formation Through Concatenation](https://leetcode.com/problems/palindrome-permutation/) | [javascript]()|[:memo:](https://leetcode.com/problems/palindrome-permutation/)|Easy|
+
+|Day 86| [426. Convert Binary Search Tree to Sorted Doubly Linked Lis](https://leetcode.com/problems/convert-binary-search-tree-to-sorted-doubly-linked-list/submissions/) | [javascript]()|[:memo:](https://leetcode.com/problems/convert-binary-search-tree-to-sorted-doubly-linked-list/submissions/)|Medium|
