Add solution for Challenge 28 by aruncs

[aruncs]

Challenge 28 Solution

Submitted by: @aruncs
Challenge: Challenge 28

Description

This PR contains my solution for Challenge 28.

Changes

• Added solution file to challenge-28/submissions/aruncs/solution-template.go

Testing

• Solution passes all test cases
• Code follows Go best practices

Thank you for reviewing my submission! 🚀

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 05dab021-5af6-44e0-bd1b-4cee1ecb4505

📥 Commits

Reviewing files that changed from the base of the PR and between 13188e6 and 57c79e6.

📒 Files selected for processing (1)

• challenge-28/submissions/aruncs/solution-template.go

🚧 Files skipped from review as they are similar to previous changes (1)

• challenge-28/submissions/aruncs/solution-template.go

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Walkthrough

Adds a Go cache library with LRU, LFU, and FIFO implementations, shared cache APIs, hit-rate metrics, a thread-safe wrapper, and policy-based factory constructors.

Changes

Cache library

Layer / File(s)	Summary
Cache contract and LRU implementation challenge-28/submissions/aruncs/solution-template.go	Defines the shared interface and policy types, then implements LRU ordering, eviction, metrics, deletion, and clearing.
LFU frequency tracking and eviction challenge-28/submissions/aruncs/solution-template.go	Tracks entries in per-frequency lists, promotes accessed entries, evicts from the least-frequency list, and supports lifecycle operations.
FIFO queue operations challenge-28/submissions/aruncs/solution-template.go	Maintains insertion order, updates existing values, evicts the oldest entry, and implements cache metrics and lifecycle operations.
Thread-safe wrapper and factories challenge-28/submissions/aruncs/solution-template.go	Serializes cache mutations, protects read methods with read locks, and adds policy-based cache construction with optional wrapping.

Estimated code review effort: 4 (Complex) | ~60 minutes

Sequence Diagram(s)

sequenceDiagram
  participant Client
  participant NewThreadSafeCacheWithPolicy
  participant NewCache
  participant ThreadSafeCache
  participant PolicyCache
  Client->>NewThreadSafeCacheWithPolicy: Provide policy and capacity
  NewThreadSafeCacheWithPolicy->>NewCache: Create LRU, LFU, or FIFO cache
  NewThreadSafeCacheWithPolicy->>ThreadSafeCache: Wrap selected cache
  Client->>ThreadSafeCache: Invoke cache operation
  ThreadSafeCache->>PolicyCache: Delegate under lock
  PolicyCache-->>Client: Return cache result

Loading

Possibly related PRs

• RezaSi/go-interview-practice#706: Implements the same Challenge 28 cache API and policy-specific caches.
• RezaSi/go-interview-practice#1611: Matches the cache types, eviction logic, metrics, factories, and thread-safe wrapper.
• RezaSi/go-interview-practice#1710: Adds the same cache module and factory structure.

Poem

I’m a rabbit with caches in a row,
LRU, LFU, FIFO all flow.
Locks guard each hop,
Factories never stop—
Bouncy cache values now go! 🐇

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately summarizes the main change: a solution submission for Challenge 28 by aruncs.
Description check	✅ Passed	The description matches the submitted Challenge 28 solution and its stated testing/results.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

Warning

There were issues while running some tools. Please review the errors and either fix the tool's configuration or disable the tool if it's a critical failure.

🔧 golangci-lint (2.12.2)

level=error msg="[linters_context] typechecking error: pattern ./...: directory prefix . does not contain main module or its selected dependencies"

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Actionable comments posted: 3

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ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 6cc6a76f-b7d4-4567-a0da-a70dfa22c9f5

📥 Commits

Reviewing files that changed from the base of the PR and between 40a90c1 and 13188e6.

📒 Files selected for processing (1)

• challenge-28/submissions/aruncs/solution-template.go

[github-actions]

🎉 Auto-merged!

This PR was automatically merged after 2 days with all checks passing.

Thank you for your contribution, @aruncs!

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