From f7bc3425516845a80e4c1e466ceab882604f3c67 Mon Sep 17 00:00:00 2001
From: bt3gl <138340846+bt3gl-cryptographer@users.noreply.github.com>
Date: Tue, 8 Aug 2023 14:18:30 -0700
Subject: [PATCH] Update bt_preorder_transversal.py

---
 trees/bt_preorder_transversal.py | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/trees/bt_preorder_transversal.py b/trees/bt_preorder_transversal.py
index c186d27..c1fd916 100644
--- a/trees/bt_preorder_transversal.py
+++ b/trees/bt_preorder_transversal.py
@@ -5,27 +5,25 @@
 
 def preorder_recursive(root: Optional[Node]) -> list[int]:
        
-        if root == None:
+        if root is none None:
                 return []
         
         return [root.val] + preorder_recursive(root.left) + preorder_recursive(root.right)
     
 
-def preorder_iterative(root: Optional[Node]) -> list[int]:
+def preorder_iterative(root) -> list:
         
         result = []
         stack = [root]
         
         while stack:
             
-            current = stack.pop()
-            result.append(current.val)
+            node = stack.pop()
             
-            if current.right:
-                stack.append(current.right)
-                
-            if current.left:
-                stack.append(current.left)
+            if node:
+                result.append(node.val) 
+                stack.append(node.left)
+                stack.append(node.right)
             
         return result