feat(bit manipulation): count number of 1 bits

[BrianLusina]

Describe your change:

Count the number of 1 bits in an integer

• Add an algorithm?
• Fix a bug or typo in an existing algorithm?
• 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.
• [x ] All new algorithms have a URL in its comments that points to Wikipedia or other similar explanation.
• If this pull request resolves one or more open issues then the commit message contains Fixes: #{$ISSUE_NO}.

Summary by CodeRabbit

• New Features

  • Added a bit manipulation function to count the number of 1-bits in 32-bit unsigned integers using an efficient bit-iteration technique.

• Documentation

  • Added comprehensive documentation including problem description, algorithm explanation, and complexity analysis with illustrative examples.

• Tests

  • Added unit tests covering multiple test cases for the new function.

_{✏️ Tip: You can customize this high-level summary in your review settings.}

[coderabbitai]

Caution

Review failed

The pull request is closed.

📝 Walkthrough

Walkthrough

A new bit manipulation algorithm "Number Of 1 Bits" is added to the codebase. The implementation counts set bits in a 32-bit integer using bit-by-bit iteration with least significant bit extraction. Supporting documentation, directory entry, and comprehensive unit tests are included. No existing code is modified.

Changes

Cohort / File(s)	Summary
Documentation & Directory DIRECTORY.md, bit_manipulation/number_of_1_bits/README.md	Directory index updated with new entry; comprehensive README added explaining the bit-counting problem, algorithm approach (LSB extraction with right-shifts), complexity analysis (O(1) time/space for 32 iterations max), and illustrative examples.
Implementation & Testing bit_manipulation/number_of_1_bits/__init__.py, bit_manipulation/number_of_1_bits/test_number_of_one_bits.py	New public function count_bits(n: int) -> int implemented using iterative LSB checking and right-shifting. Parameterized unit tests with multiple test cases validate correctness across various 32/64-bit integer inputs.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

Suggested labels

enhancement

Poem

🐰 Counting ones with whisker precision,
Shift right, check the bit with decision,
Each LSB that glimmers so bright,
We tally them all through the algorithmic night! ✨

✨ Finishing touches

• 📝 Generate docstrings

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📜 Recent review details

Configuration used: defaults

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 629a536 and 55c8a09.

⛔ Files ignored due to path filters (15)

• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_1.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_10.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_11.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_12.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_13.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_14.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_15.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_2.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_3.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_4.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_5.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_6.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_7.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_8.png is excluded by !**/*.png
• bit_manipulation/number_of_1_bits/images/solutions/number_of_one_bits_solution_9.png is excluded by !**/*.png

📒 Files selected for processing (4)

• DIRECTORY.md
• bit_manipulation/number_of_1_bits/README.md
• bit_manipulation/number_of_1_bits/__init__.py
• bit_manipulation/number_of_1_bits/test_number_of_one_bits.py

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