Add solution for Challenge 19 by yz4230

[yz4230]

Challenge 19 Solution

Submitted by: @yz4230
Challenge: Challenge 19

Description

This PR contains my solution for Challenge 19.

Changes

• Added solution file to challenge-19/submissions/yz4230/solution-template.go

Testing

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

Thank you for reviewing my submission! 🚀

[coderabbitai]

Walkthrough

Adds a new Go solution file to challenge-19 containing four exported utility functions for integer slice operations: FindMax (returns maximum value), RemoveDuplicates (removes duplicates while preserving order), ReverseSlice (reverses elements), and FilterEven (filters even numbers). Includes a main function demonstrating these utilities.

Changes

Cohort / File(s)	Summary
Challenge-19 Solution challenge-19/submissions/yz4230/solution-template.go	New file with four exported utility functions for integer slice operations (FindMax, RemoveDuplicates, ReverseSlice, FilterEven) and a demonstration main function

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~8 minutes

• Code is straightforward with clear, independent utility functions
• No complex logic or edge case handling beyond empty slice checks
• Verify correctness of algorithms: especially RemoveDuplicates order preservation and ReverseSlice implementation

Possibly related PRs

• Add solution for Challenge 19 by kiramux #722: Implements the same four slice utility functions (FindMax, RemoveDuplicates, ReverseSlice, FilterEven) in a different challenge-19 submission path.
• Add solution for Challenge 19 by iamsurajmandal #716: Adds identical utility functions with demonstration main across different challenge-19 submission directories.
• Add solution for Challenge 19 by Johrespi #724: Implements the same four exported functions with identical signatures and behaviors in challenge-19 submissions.

Pre-merge checks

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and specifically describes the main change: adding a solution for Challenge 19 by a specific user.
Description check	✅ Passed	The description is directly related to the changeset, providing context about the Challenge 19 solution submission with details about changes and testing.
Docstring Coverage	✅ Passed	Docstring coverage is 80.00% which is sufficient. The required threshold is 80.00%.

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Actionable comments posted: 0

🧹 Nitpick comments (1)

challenge-19/submissions/yz4230/solution-template.go (1)

60-67: Consider preallocating with length for better performance.

The logic is correct, but since the final size is known, you can improve performance by preallocating the slice with the correct length and using direct assignment instead of append.

Apply this diff to improve performance:

-func ReverseSlice(slice []int) []int {
-	ret := make([]int, 0, len(slice))
-	for i := range slice {
-	    ret = append(ret, slice[len(slice)-i-1])
-	}
-	return ret
-}
+func ReverseSlice(slice []int) []int {
+	ret := make([]int, len(slice))
+	for i := range slice {
+	    ret[i] = slice[len(slice)-i-1]
+	}
+	return ret
+}

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between ca8ea29 and 82ae4b2.

📒 Files selected for processing (1)

• challenge-19/submissions/yz4230/solution-template.go (1 hunks)

🔇 Additional comments (4)

challenge-19/submissions/yz4230/solution-template.go (4)

8-27: LGTM!

The demonstration code appropriately tests all utility functions with a sample dataset.

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29-44: LGTM!

The implementation correctly handles empty slices and uses math.MinInt as the initial value, which is a good practice for finding the maximum in an integer slice.

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46-58: LGTM!

The implementation correctly removes duplicates while preserving order, and efficiently uses map[int]struct{}{} for tracking seen values.

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69-79: LGTM!

The implementation correctly filters even numbers and efficiently preallocates the slice capacity.