binary tree using traversal lists #13774

night007-hub · 2025-10-26T12:37:30Z

Describe your change:

Add an algorithm?
Fix a bug or typo in an existing algorithm?
Add or change doctests? -- Note: Please avoid changing both code and tests in a single pull request.
Documentation change?

Checklist:

I have read CONTRIBUTING.md.
This pull request is all my own work -- I have not plagiarized.
I know that pull requests will not be merged if they fail the automated tests.
This PR only changes one algorithm file. To ease review, please open separate PRs for separate algorithms.
All new Python files are placed inside an existing directory.
All filenames are in all lowercase characters with no spaces or dashes.
All functions and variable names follow Python naming conventions.
All function parameters and return values are annotated with Python type hints.
All functions have doctests that pass the automated testing.
All new algorithms include at least one URL that points to Wikipedia or another similar explanation.
If this pull request resolves one or more open issues then the description above includes the issue number(s) with a closing keyword: "Fixes #ISSUE-NUMBER".

for more information, see https://pre-commit.ci

algorithms-keeper

Click here to look at the relevant links ⬇️

🔗 Relevant Links

Repository:

Contributing guidelines

Project Euler solution guidelines

Python:

Formatted string literals (f-strings)

Type hints

doctest

unittest

pytest

Automated review generated by algorithms-keeper. If there's any problem regarding this review, please open an issue about it.

algorithms-keeper commands and options

algorithms-keeper actions can be triggered by commenting on this PR:

@algorithms-keeper review to trigger the checks for only added pull request files

@algorithms-keeper review-all to trigger the checks for all the pull request files, including the modified files. As we cannot post review comments on lines not part of the diff, this command will post all the messages in one comment.

NOTE: Commands are in beta and so this feature is restricted only to a member or owner of the organization.

algorithms-keeper · 2025-10-26T12:37:35Z

data_structures/binary_tree/build_tree_from_traversal.py

+ self.parent: Node | None = None
+
+
+def inorder_traversal(root: Node | None, out: list[int]) -> None:


As there is no test file in this pull request nor any test function or class in the file data_structures/binary_tree/build_tree_from_traversal.py, please provide doctest for the function inorder_traversal

algorithms-keeper · 2025-10-26T12:37:35Z

data_structures/binary_tree/build_tree_from_traversal.py

+ inorder_traversal(root.right, out)
+
+
+def _build_tree_from_preorder(


As there is no test file in this pull request nor any test function or class in the file data_structures/binary_tree/build_tree_from_traversal.py, please provide doctest for the function _build_tree_from_preorder

algorithms-keeper · 2025-10-26T12:37:35Z

data_structures/binary_tree/build_tree_from_traversal.py

+ return root
+
+
+def build_tree_from_preorder(inorder: list[int], preorder: list[int]) -> Node | None:


As there is no test file in this pull request nor any test function or class in the file data_structures/binary_tree/build_tree_from_traversal.py, please provide doctest for the function build_tree_from_preorder

algorithms-keeper · 2025-10-26T12:37:36Z

data_structures/binary_tree/build_tree_from_traversal.py

+ return root
+
+
+def build_tree_from_postorder(inorder: list[int], postorder: list[int]) -> Node | None:


As there is no test file in this pull request nor any test function or class in the file data_structures/binary_tree/build_tree_from_traversal.py, please provide doctest for the function build_tree_from_postorder

algorithms-keeper

Click here to look at the relevant links ⬇️

🔗 Relevant Links

Repository:

Contributing guidelines

Project Euler solution guidelines

Python:

Formatted string literals (f-strings)

Type hints

doctest

unittest

pytest

Automated review generated by algorithms-keeper. If there's any problem regarding this review, please open an issue about it.

algorithms-keeper commands and options

algorithms-keeper actions can be triggered by commenting on this PR:

@algorithms-keeper review to trigger the checks for only added pull request files

@algorithms-keeper review-all to trigger the checks for all the pull request files, including the modified files. As we cannot post review comments on lines not part of the diff, this command will post all the messages in one comment.

NOTE: Commands are in beta and so this feature is restricted only to a member or owner of the organization.

algorithms-keeper · 2025-10-26T12:50:28Z

data_structures/binary_tree/build_tree_from_traversal.py

+ self.parent: Node | None = None
+
+
+def inorder_traversal(root: Node | None, out: list[int]) -> None:


As there is no test file in this pull request nor any test function or class in the file data_structures/binary_tree/build_tree_from_traversal.py, please provide doctest for the function inorder_traversal

algorithms-keeper · 2025-10-26T12:50:28Z

data_structures/binary_tree/build_tree_from_traversal.py

+ inorder_traversal(root.right, out)
+
+
+def _build_tree_from_preorder(


As there is no test file in this pull request nor any test function or class in the file data_structures/binary_tree/build_tree_from_traversal.py, please provide doctest for the function _build_tree_from_preorder

algorithms-keeper · 2025-10-26T12:50:28Z

data_structures/binary_tree/build_tree_from_traversal.py

+ return root
+
+
+def build_tree_from_preorder(inorder: list[int], preorder: list[int]) -> Node | None:


As there is no test file in this pull request nor any test function or class in the file data_structures/binary_tree/build_tree_from_traversal.py, please provide doctest for the function build_tree_from_preorder

algorithms-keeper · 2025-10-26T12:50:29Z

data_structures/binary_tree/build_tree_from_traversal.py

+ return root
+
+
+def build_tree_from_postorder(inorder: list[int], postorder: list[int]) -> Node | None:


As there is no test file in this pull request nor any test function or class in the file data_structures/binary_tree/build_tree_from_traversal.py, please provide doctest for the function build_tree_from_postorder

night007-hub and others added 5 commits October 26, 2025 16:58

build tree using traversals

1ec0ff0

[pre-commit.ci] auto fixes from pre-commit.com hooks

a7bb97c

for more information, see https://pre-commit.ci

build tree from traversals new

5702627

final build tree

dff30d0

[pre-commit.ci] auto fixes from pre-commit.com hooks

ee149d6

for more information, see https://pre-commit.ci

algorithms-keeper bot added require tests Tests [doctest/unittest/pytest] are required awaiting reviews This PR is ready to be reviewed labels Oct 26, 2025

algorithms-keeper bot reviewed Oct 26, 2025

View reviewed changes

algorithms-keeper bot added the tests are failing Do not merge until tests pass label Oct 26, 2025

final2 changes

2ffa548

algorithms-keeper bot reviewed Oct 26, 2025

View reviewed changes

algorithms-keeper bot removed the tests are failing Do not merge until tests pass label Oct 26, 2025

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

Uh oh!

Uh oh!

binary tree using traversal lists #13774

binary tree using traversal lists #13774

night007-hub commented Oct 26, 2025

algorithms-keeper bot left a comment

algorithms-keeper bot Oct 26, 2025

algorithms-keeper bot Oct 26, 2025

algorithms-keeper bot Oct 26, 2025

algorithms-keeper bot Oct 26, 2025

algorithms-keeper bot left a comment

algorithms-keeper bot Oct 26, 2025

algorithms-keeper bot Oct 26, 2025

algorithms-keeper bot Oct 26, 2025

algorithms-keeper bot Oct 26, 2025

Labels

1 participant

		self.parent: Node \| None = None


		def inorder_traversal(root: Node \| None, out: list[int]) -> None:

		inorder_traversal(root.right, out)


		def _build_tree_from_preorder(

		return root


		def build_tree_from_preorder(inorder: list[int], preorder: list[int]) -> Node \| None:

		return root


		def build_tree_from_postorder(inorder: list[int], postorder: list[int]) -> Node \| None:

Uh oh!

Uh oh!

binary tree using traversal lists #13774

Are you sure you want to change the base?

binary tree using traversal lists #13774

Conversation

night007-hub commented Oct 26, 2025

Describe your change:

Checklist:

algorithms-keeper bot left a comment

Choose a reason for hiding this comment

🔗 Relevant Links

Repository:

Python:

Automated review generated by algorithms-keeper. If there's any problem regarding this review, please open an issue about it.

algorithms-keeper actions can be triggered by commenting on this PR:

algorithms-keeper bot Oct 26, 2025

Choose a reason for hiding this comment

algorithms-keeper bot Oct 26, 2025

Choose a reason for hiding this comment

algorithms-keeper bot Oct 26, 2025

Choose a reason for hiding this comment

algorithms-keeper bot Oct 26, 2025

Choose a reason for hiding this comment

algorithms-keeper bot left a comment

Choose a reason for hiding this comment

🔗 Relevant Links

Repository:

Python:

Automated review generated by algorithms-keeper. If there's any problem regarding this review, please open an issue about it.

algorithms-keeper actions can be triggered by commenting on this PR:

algorithms-keeper bot Oct 26, 2025

Choose a reason for hiding this comment

algorithms-keeper bot Oct 26, 2025

Choose a reason for hiding this comment

algorithms-keeper bot Oct 26, 2025

Choose a reason for hiding this comment

algorithms-keeper bot Oct 26, 2025

Choose a reason for hiding this comment

Labels

1 participant