Time: 63 ms (10.59%), Space: 49.4 MB (7.64%) - LeetHub

Author: hogan-tech

0144-binary-tree-preorder-traversal/0144-binary-tree-preorder-traversal.js

@@ -0,0 +1,24 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val, left, right) {
+ *     this.val = (val===undefined ? 0 : val)
+ *     this.left = (left===undefined ? null : left)
+ *     this.right = (right===undefined ? null : right)
+ * }
+ */
+/**
+ * @param {TreeNode} root
+ * @return {number[]}
+ */
+var preorderTraversal = function(root) {
+    const result = [];
+    function preorder(node) {
+        if (node) {
+            result.push(node.val);
+            preorder(node.left);
+            preorder(node.right);
+        }
+    }
+    preorder(root);
+    return result;
+};