Create 0145-binary-tree-postorder-traversal.py

nick322 · Mar 19, 2023 · 3ae21e2 · 3ae21e2
1 parent 2dd06cd
commit 3ae21e2
Showing 1 changed file with 19 additions and 0 deletions.
diff --git a/python/0145-binary-tree-postorder-traversal.py b/python/0145-binary-tree-postorder-traversal.py
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+class Solution:
+ def postorderTraversal(self, root: Optional[TreeNode]) -> List[int]:
+ stack = [root]
+ visit = [False]
+ res = []
+
+ while stack:
+ cur, v = stack.pop(), visit.pop()
+ if cur:
+ if v:
+ res.append(cur.val)
+ else:
+ stack.append(cur)
+ visit.append(True)
+ stack.append(cur.right)
+ visit.append(False)
+ stack.append(cur.left)
+ visit.append(False)
+ return res