* hyphen_files = [file for file in filepaths if "-" in file]

* updating DIRECTORY.md

* Rename recursive-quick-sort.py to recursive_quick_sort.py

* updating DIRECTORY.md

* Rename aho-corasick.py to aho_corasick.py

* updating DIRECTORY.md

* Rename polynom-for-points.py to polynom_for_points.py

* updating DIRECTORY.md

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* bin_to_octal

Converts binary values to the octal equivalent.

* Update bin_to_octal

* Update conversions/bin_to_octal

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* Update conversions/bin_to_octal

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* Update conversions/bin_to_octal

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* Update conversions/bin_to_octal

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* Rename bin_to_octal to bin_to_octal.py

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* Update and rename bin_to_octal.py to binary_to_octal.py

* fixup! Format Python code with psf/black push

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…m a palindrome. (#2450)

* Added check_if_string_can_be_rearranged_as_palindrome function.

* Added counter implementation and benchmark function.

* flake changes

* Update and rename check_if_string_can_be_converted_to_palindrome.py to can_string_be_rearranged_as_palindrome.py

* Update can_string_be_rearranged_as_palindrome.py

* #

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* Add solution and test files for project euler 54

* Update sol1.py

* updating DIRECTORY.md

* Fix: use proper path to open files

* Commit suggestions:

- Use list comprehension instead of map
- Sort imports using isort

* Changes made as suggested (simplified a lot):

- List and set comprehension instead of itemgetter
- Using enumerate as it's easy to read
- Divided into list of card values and set of card suit as set will
  remove all the duplicate values. So, no need for double indexing.
- Add test for testing multiple calls to five_high_straight function

* Add suggestions and simplified:

- Split generate_random_hands function into two:
  - First will generate a random hand
  - Second, which will be called, will return a generator object

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* optimization for problem09 in project_euler

* added benchmark code

* fixup! Format Python code with psf/black push

* Update project_euler/problem_09/sol1.py

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* updating DIRECTORY.md

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* Testing Travis CI configuration for project Euler

* Fix: Installing mypy and pytest-cov for testing

* Remove unnecessary checks for project_euler job

* Removing branches section

* Update .travis.yml

* Update .travis.yml

* Update .travis.yml

* Update .travis.yml

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* from __future__ import annotations

* fixup! from __future__ import annotations

* fixup! from __future__ import annotations

* fixup! Format Python code with psf/black push

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* Add Python type hints and doctests to other/two_sum.py

#2465

* Update other/two_sum.py

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* Update other/two_sum.py

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* Update two_sum.py

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* Added binary_and_operator.py & binary_xor_operator.py

* Updated binary_and_operator.py

* Updated binary_xor_operator.py

* Updated binary_xor_operator.py

* updated reversed words

* fixup! Format Python code with psf/black push

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* fixed remove duplicate

* fixup! Format Python code with psf/black push

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* Add solution() for problem 54 of Project Euler

* Add type hints for solution() function

* wiggle sort : type hint + doctest

* fixed function name in docstring

* correction

* Create __init__.py

* Add files via upload

* Update sol1.py

* Update sol1.py

* Update sol1.py

* Update project_euler/problem_97/sol1.py

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* Update sol1.py

* Update project_euler/problem_97/sol1.py

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* added type hints and doctests for minimax algorithm

* Update backtracking/minimax.py

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* last fix

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* fixed bug

* fixup! Format Python code with psf/black push

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* Updated singly_linked_list

* fixup! Format Python code with psf/black push

* undo __repr__

* updating DIRECTORY.md

* UNTESTED CHANGES: Add an .__iter__() method.

This will break tests, etc.

* fixup! Format Python code with psf/black push

* len(tuple(iter(self)))

* fixed __repr__()

* Update data_structures/linked_list/singly_linked_list.py

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* Update data_structures/linked_list/singly_linked_list.py

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* Update data_structures/linked_list/singly_linked_list.py

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* Update data_structures/linked_list/singly_linked_list.py

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* Update data_structures/linked_list/singly_linked_list.py

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* Update data_structures/linked_list/singly_linked_list.py

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* Update data_structures/linked_list/singly_linked_list.py

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* * fixed __getitem__() function
* add test

* * updated doctests
* updated __setitem__() func

* fixup! Format Python code with psf/black push

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* Update morse_code_implementation.py

Added more characters to MORSE_CODE_DICT for a more complete dictionary.
Split words with "/" instead of a space as is standard.
Fixed bug when encrypting a message with a comma.

* Fixed comment typo

* update lower and upper

* fixup! Format Python code with psf/black push

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* Use self-documenting option instead of cryptic option

@mateuszz0000 Your review, please.  Pretend that you do not know what `-L` stands for.  How many keystrokes and clicks does it take to confirm the purpose of this option?

* updating DIRECTORY.md

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* Updated circular_linked_list

* fixup! Format Python code with psf/black push

* Update data_structures/linked_list/circular_linked_list.py

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* updating DIRECTORY.md

* delete print_list()

* test is_empty()

* test is_empty return False

* fixup! Format Python code with psf/black push

* fixed indentation

* fixup! Format Python code with psf/black push

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* Stock market prediction using greadient boosting

* To reverse a string using stack

* To reverse string using stack

* Predict Stock Prices Python & Machine Learning

* Gradient boosting regressor on boston dataset

* Gradient boosting regressor implementation

* Gradient boosting regressor

* Gradient boosting regressor

* Gradient boosting regressor

* Removing files

* GradientBoostingRegressor example

* Demo Gradient Boosting

* Demo Gradient boosting

* demo of gradient boosting

* gradient boosting demo

* Fix spelling mistake

* Fix formatting

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* optimization for pangram string

* fixup! Format Python code with psf/black push

* Update strings/check_pangram.py

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* updating DIRECTORY.md

* Update strings/check_pangram.py

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* Add file for testing Project Euler solutions

* Remove the importlib import

* Update project_euler/solution_test.py

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* Small tweaks to project_euler/solution_test.py

* Test Project Euler solutions through Travis

* Improved testing for Project Euler solutions:

- Renamed file so that it isn't picked up by pytest
- Fail fast on validating solutions through Travis CI

* Update validate_solutions.py

* Use namedtuple for input parameters and answer

- Remove logging
- Remove unnecessary checks for PROJECT_EULER_PATH as Travis CI
  picks up the same path

* Fix flake8 errors: line too long

* Small tweaks to validate_solutions.py

* Add all answers & back to using dictionary

* Using pytest for testing Project Euler solutions

- As we want to fail fast on testing solutions, we need to test using
  this script first before we use tests written by the author.
- As pytest stops testing as soon as it receives a traceback, we need to
  use pytest-subtests to tell pytest to test all the iterations for the
  function with given parameters.

* Print error messages in oneline format

* Separated answers into a separate file:

- Add custom print function to print all the error messages at the
  end of all the tests
- Let Travis skip if this failed

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* Create vector3_for_2d_rendering.py

Edited for passing travis test

* Delete vector3_for_2d_rendering.py

* Create vector3_for_2d_rendering.py

* Update vector3_for_2d_rendering.py

Compressed the line 19 to 28 into 19 to 21

* Update vector3_for_2d_rendering.py

* Update vector3_for_2d_rendering.py

* Update vector3_for_2d_rendering.py

completly corrected pep8 errors using Pycharm IDE

* Update vector3_for_2d_rendering.py

* Update graphics/vector3_for_2d_rendering.py

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* Update graphics/vector3_for_2d_rendering.py

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* Update graphics/vector3_for_2d_rendering.py

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* Update vector3_for_2d_rendering.py

* Update vector3_for_2d_rendering.py

* Update graphics/vector3_for_2d_rendering.py

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* Update graphics/vector3_for_2d_rendering.py

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* Apply suggestions from code review

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* Update vector3_for_2d_rendering.py

Added A few extra names to __author__ 😄

* Update vector3_for_2d_rendering.py

Used Pycharm to fix PEP8 errors, doctest errors

* Update vector3_for_2d_rendering.py

Added enough doctests

* Update graphics/vector3_for_2d_rendering.py

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* Remove second main()

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* Add type hints for strings/ folder

* Rerun other checks

* updating DIRECTORY.md

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Rename the main solution functions to solution.
Rename prime chec functions to is_prime.
Add default args, typehints, expand variable names.

…03 (#2917)

* Fix typehints in project_euler/problem01

Squashed commit of the following:

commit 6801d07
Author: Archaengel <god11341258@gmail.com>
Date:   Mon Oct 5 16:40:10 2020 -0700

    Fix typehints in project_euler/problem01

commit 29afc3a
Author: Archaengel <god11341258@gmail.com>
Date:   Mon Oct 5 15:06:34 2020 -0700

    Add typehints and default argument for project_euler/problem_01

* Add default args, typehints, and expand variable names for PE prob 02

* Add style improvements for first solution of PE Problem 02

* Add default arg and typehints for second solution of PE Problem 02

* Add default arg for third solution of PE Problem 02

* Add style improvements for 1st soln of PE problem 03

* Add default arg and typehints for 2nd soln of PE problem 03

* Add default arg for 3rd soln of PE problem 03

* Remove unnecessary newlines

* Remove unnecessary newlines

* Fix end of file for 2nd soln in PE problem 03

* add typehints and docstrings

* add typehint and default value

* add typehint and default value. Removed unused variable.

* do not modifiy the given solution

* add doctests

* update sol1 after running black

* add typehint, docstring, and doctest

* update sol2 after running black

- Add default arguments to solution function
- Add link to Project Euler problem 6
- Add doctest for testing `solution()`
- Removed test_solutions.py as it is redundant

* Fix typehints in project_euler/problem01

Squashed commit of the following:

commit 6801d07
Author: Archaengel <god11341258@gmail.com>
Date:   Mon Oct 5 16:40:10 2020 -0700

    Fix typehints in project_euler/problem01

commit 29afc3a
Author: Archaengel <god11341258@gmail.com>
Date:   Mon Oct 5 15:06:34 2020 -0700

    Add typehints and default argument for project_euler/problem_01

* Add default args, typehints, and expand variable names for PE prob 02

* Add style improvements for first solution of PE Problem 02

* Add default arg and typehints for second solution of PE Problem 02

* Add default arg for third solution of PE Problem 02

* Add style improvements for 1st soln of PE problem 03

* Add default arg and typehints for 2nd soln of PE problem 03

* Add default arg for 3rd soln of PE problem 03

* Remove unnecessary newlines

* Remove unnecessary newlines

* Fix end of file for 2nd soln in PE problem 03

* Add style improvements to solutions for PE problem 04

* Restore original newlines in soln for PE problem 04

* Fix punctuation in docstring for PE problem 04

* Restore solution bodies for PE problem 04

* Expand variable names for 2nd soln of PE problem 04

* add type hints to math/extended euclid

* math/extended euclid - add doctest

* math/extended euclid: remove manual doctest

* change algorithm for negative numbers

* improve naming of variables

* Update extended_euclidean_algorithm.py

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- Improved variable names
- Added type hints
- Added default argument values for validate_solutions script

* Added doomsday algorithm

* Adding unit-tests to doomsday algorithm

* running black on doomsday

* adding doctest and fixing a black issue [doomsday]

* Update doomsday.py

* fixing black issue [doomsday]

* Update other/doomsday.py

* Update doomsday.py

* adding more doctests (following review comment) [doomsday]

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Add default arguments, typehints and rename solution function for Porject Euler Problem 28

* fix code style in problem 76

Signed-off-by: joan.rosellr <joan.rosellr@gmail.com>

* Update sol1.py

* Update sol1.py

* Remove trailing whitespace

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* Fix: Corrected test. List in test must be ordered.

* Add tests with big lists.

* fix code style and update problem description with link

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* Update sol1.py

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* name method solution in project_euler/problem99

* rename function

* add type hints and default args for problem 5

* Update sol1.py

* Update sol2.py

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* add typehints and docstrings

* add typehint and default value

* add typehint and default value. Removed unused variable.

* do not modifiy the given solution

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* update sol1 after running black

* add typehint, docstring, and doctest

* update sol2 after running black

* add full problem statement and solution function with typehint and doctest

* renamed original function instead of adding new one

* don't alter original solution

* Fix: Multiple errors in fibonacci search.

- Test lists were not ordered, this is required for Fibonacci search
- Place documentation of function inside function
- Create multiple different tests including, float, char and negatives
- Add type hints in line with #2128

* Fix: sort of modules and delete typehint.

* Apply suggestions from code review

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* Correct invocation of lru_cache.

* Add check for input in fibonacci and doctest.

* Correct typehints to comply to numpy style.

* Correct ValueError to TypeError.

Co-authored-by: Dhruv <dhruvmanila@gmail.com>

* Correct doctest for TypeError.

* Rename  single letter names as mentioned in CONTRIBUTING.md.

* Fix: Bug in big lists.

* Remove print(.) in doctests.

* Refactor iterator to while loop.

* Update searches/fibonacci_search.py

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* add solution method

* fix formatting

- Add default argument values
- Add type hints
- Change one letter variable names to a more descriptive one
- Add doctest for `solution()`

* add problem title and link, fix f-string

Signed-off-by: joan.rosellr <joan.rosellr@gmail.com>

* fix code style and improve doctests

Signed-off-by: joan.rosellr <joan.rosellr@gmail.com>

* undo changes to the main call

Signed-off-by: joan.rosellr <joan.rosellr@gmail.com>

* remove assignment operator in f-string

Signed-off-by: joan.rosellr <joan.rosellr@gmail.com>

* add newline after first import to attempt to fix pre-commit workflow

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* undo doctest changes, rename compute_pandigital_primes to solution

Signed-off-by: joan.rosellr <joan.rosellr@gmail.com>

* update solution to return the actual solution instead of a list

Signed-off-by: joan.rosellr <joan.rosellr@gmail.com>

* Update sol1.py

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* add default arguments and problem url

* Update and rename problem_27_sol1.py to sol1.py

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…#2443)

* test/graphs/kruskal: adding a test case to verify the correctness of the algorithm

Fixes #2128

* grahps/kruskal: running psf/black

* graphs/kruskal: read edges in a friendlier fashion

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* Update minimum_spanning_tree_kruskal.py

* fixup! Format Python code with psf/black push

* Update test_min_spanning_tree_kruskal.py

* updating DIRECTORY.md

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Co-authored-by: John Law <johnlaw.po@gmail.com>
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