* pre-commit: Upgrade psf/black for stable style 2023
Updating https://github.com/psf/black ... updating 22.12.0 -> 23.1.0 for their `2023 stable style`.
* https://github.com/psf/black/blob/main/CHANGES.md#2310
> This is the first [psf/black] release of 2023, and following our stability policy, it comes with a number of improvements to our stable style…
Also, add https://github.com/tox-dev/pyproject-fmt and https://github.com/abravalheri/validate-pyproject to pre-commit.
I only modified `.pre-commit-config.yaml` and all other files were modified by pre-commit.ci and psf/black.
* [pre-commit.ci] auto fixes from pre-commit.com hooks
for more information, see https://pre-commit.ci
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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
* Update queue implementation
Popping the first element of a list takes O(n) time.
Using a cyclic queue takes O(1) time.
* Add queue changes from extra files
* Update indentation
* Add empty line between imports
* Fix lines
* Apply suggestions from code review
Co-authored-by: John Law <johnlaw.po@gmail.com>
Co-authored-by: John Law <johnlaw.po@gmail.com>
* Tighten up psf/black and flake8
* Fix some tests
* Fix some E741
* Fix some E741
* updating DIRECTORY.md
Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
* organized graph algorithms
* all graph algorithms in Graphs/ folder
* all graph algorithms are in one folder
* Rename number theory/factorial_python.py to maths/factorial_python.py
