feat(algorithms, binary-search): divide chocolate

[BrianLusina]

Describe your change:

Divide chocolate algorithm problem

• 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.
• 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 Divide Chocolate algorithm module with binary-search-based implementations to maximize minimum sweetness.

• Documentation

  • New README detailing problem, approach, complexity, constraints, and implementation guidance.

• Tests

  • Added parameterized unit tests covering multiple scenarios for the new algorithm.

• Style

  • Minor formatting change to a string literal.

• Chores

  • Updated directory index to include the new Divide Chocolate entry.

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

[coderabbitai]

Caution

Review failed

The pull request is closed.

Walkthrough

The PR adds a new "Divide Chocolate" problem under binary search (implementation, README, tests) and updates the directory; plus a cosmetic quote change in an unrelated interval module.

Changes

Cohort / File(s)	Summary
Divide Chocolate Implementation algorithms/search/binary_search/divide_chocolate/README.md, algorithms/search/binary_search/divide_chocolate/__init__.py, algorithms/search/binary_search/divide_chocolate/test_divide_chocolate.py	New problem folder: README describing binary-search-over-answer approach; module adds maximize_sweetness, maximize_sweetness_2, and can_divide; parameterized unit tests validating both implementations. Review attention: correctness of boundary conditions, off-by-one in binary search, and test coverage edge cases.
Directory Structure DIRECTORY.md	Inserted new nested entry "Divide Chocolate" under Binary Search linking the test file.
Cosmetic Change algorithms/intervals/remove_intervals/__init__.py	Minor formatting change: switched '-inf' to "-inf"; no behavioral change.

Sequence Diagram(s)

(omitted — changes are self-contained algorithm and tests without multi-component control-flow that would benefit from a sequence diagram)

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Possibly related PRs

• feat(algorithms, binary-search): divide chocolate #126 — Adds the same divide_chocolate module, tests, and README (appears to be a duplicate or closely related implementation).

Pre-merge checks and finishing touches

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%.	You can run @coderabbitai generate docstrings to improve docstring coverage.

✅ Passed checks (2 passed)

Check name	Status	Explanation
Title check	✅ Passed	The pull request title clearly and concisely describes the main change: adding the divide chocolate algorithm to the binary search section.
Description check	✅ Passed	The pull request description includes the required template sections and checklist with most items marked complete, accurately reflecting the changes made (algorithm addition, documentation, directory update).

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📜 Recent review details

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Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 06f1fe2 and f918257.

📒 Files selected for processing (1)

• algorithms/search/binary_search/divide_chocolate/__init__.py

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[coderabbitai]

Actionable comments posted: 2

🧹 Nitpick comments (1)

algorithms/search/binary_search/divide_chocolate/README.md (1)

50-52: Minor naming inconsistency.

The documentation refers to canDivide (camelCase), but the actual implementation uses can_divide (snake_case). The implementation correctly follows Python naming conventions. Consider updating the documentation to match: "Use the helper function can_divide(sweetness, k, mid)..."

📜 Review details

Configuration used: defaults

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 332e060 and 06f1fe2.

📒 Files selected for processing (5)

• DIRECTORY.md
• algorithms/intervals/remove_intervals/__init__.py
• algorithms/search/binary_search/divide_chocolate/README.md
• algorithms/search/binary_search/divide_chocolate/__init__.py
• algorithms/search/binary_search/divide_chocolate/test_divide_chocolate.py

🧰 Additional context used

🧬 Code graph analysis (2)

algorithms/search/binary_search/divide_chocolate/test_divide_chocolate.py (1)

algorithms/search/binary_search/divide_chocolate/__init__.py (2)

• maximize_sweetness (4-33)
• maximize_sweetness_2 (36-54)

algorithms/search/binary_search/divide_chocolate/__init__.py (1)

algorithms/search/trie/search_suggestions/__init__.py (1)

• lower_bound (5-24)

🪛 LanguageTool

algorithms/search/binary_search/divide_chocolate/README.md

[style] ~4-~4: Consider a more expressive alternative.
Context: ... share the chocolate with k friends. To do this, you’ll make k cuts to divide the ...

(DO_ACHIEVE)

🪛 markdownlint-cli2 (0.18.1)

DIRECTORY.md

123-123: Unordered list indentation
Expected: 4; Actual: 6

(MD007, ul-indent)

---

124-124: Unordered list indentation
Expected: 6; Actual: 8

(MD007, ul-indent)

🔇 Additional comments (4)

DIRECTORY.md (1)

123-124: LGTM!

The directory entry correctly documents the new "Divide Chocolate" feature under Binary Search. The indentation is consistent with other entries in this section.

algorithms/search/binary_search/divide_chocolate/__init__.py (2)

4-33: LGTM!

The binary search implementation is correct. The + 1 in line 19's mid calculation (mid = (lower_bound + upper_bound + 1) // 2) is crucial to prevent infinite loops when lower_bound and upper_bound are adjacent values. The inline feasibility check efficiently counts pieces without a separate helper function.

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36-54: LGTM!

This alternative binary search implementation is also correct and uses a different but equally valid pattern (tracking result separately with while low <= high). Having both implementations demonstrates different approaches to the same problem, which is educational.

algorithms/search/binary_search/divide_chocolate/test_divide_chocolate.py (1)

1-28: LGTM!

Excellent test coverage with parameterized tests validating both implementations against the same test cases. The test cases cover important scenarios including edge cases (k=0, uniform sweetness, etc.). This ensures both maximize_sweetness and maximize_sweetness_2 produce consistent results.