From 092700f5661326677e06d0d9c59f10fa7b322ada Mon Sep 17 00:00:00 2001
From: bt3gl <138340846+bt3gl-google@users.noreply.github.com>
Date: Sun, 30 Jul 2023 15:52:59 -0700
Subject: [PATCH] Update preorder_transversal.py

---
 trees_and_graphs/preorder_transversal.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/trees_and_graphs/preorder_transversal.py b/trees_and_graphs/preorder_transversal.py
index 09c26d5..9e2f7bc 100644
--- a/trees_and_graphs/preorder_transversal.py
+++ b/trees_and_graphs/preorder_transversal.py
@@ -1,3 +1,7 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# author: bt3gl
+
 # recursive and iterative inorder traversal
 
 def preorder_recursive(root: Optional[TreeNode]) -> list[int]: