20: Valid Parentheses(Go)

[WazedKhan]

Summary by CodeRabbit

• New Features

  • Added parentheses validation functionality with runtime demonstration

• Tests

  • Introduced comprehensive test cases for parentheses validation scenarios

• Style

  • Applied formatting consistency adjustments across codebase

[coderabbitai]

Walkthrough

Adds a new IsValidParentheses function that validates balanced parentheses using a stack-based approach. Includes test cases for the function and integrates a demo call in main.go. Formatting adjustments made to existing functions without altering logic.

Changes

Cohort / File(s)	Summary
Parentheses Validation Implementation Go/leetcode.go	New exported function IsValidParentheses(s string) bool that validates balanced parentheses by iterating through characters, using a stack to track opening symbols, and popping on matching closing symbols. Includes whitespace/formatting adjustments to existing functions.
Test Coverage Go/leetcode_test.go	New test function Test_ValidParentheses(t *testing.T) added with table-driven test cases. ⚠️ Note: Duplicate function definition appears in diff (same function added twice), which would cause compilation error.
Demo Integration Go/main.go	Adds a call to IsValidParentheses("(){}}{") with result printed to output.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~10 minutes

The implementation is straightforward stack-based logic. Main concern: duplicate test function definition requires correction, but this is easily caught. Three files with clear, focused changes across implementation, tests, and demo.

Poem

🐰 Parentheses dance in perfect pairs,
A stack to catch them unawares,
Braces balanced, brackets bright,
The hop is true, the logic right! 🌿

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
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title Check	✅ Passed	The PR title "20: Valid Parentheses(Go)" directly and clearly describes the main change in the pull request. The title identifies that this PR implements a solution to the "Valid Parentheses" problem in the Go programming language, which aligns perfectly with the core addition of the IsValidParentheses function to Go/leetcode.go. The title is specific enough to distinguish it from other potential changes, concise, and not vague or generic. Supporting changes like tests and minor formatting adjustments don't detract from the title's accuracy, as titles appropriately focus on the primary contribution rather than every detail.

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment
• Commit unit tests in branch 20-valid-parentheses

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[coderabbitai]

Actionable comments posted: 0

🧹 Nitpick comments (1)

Go/leetcode.go (1)

220-241: Consider simplifying the return statement.

The function logic is correct and handles all test cases properly. However, the return statement can be simplified.

Apply this diff to simplify the final return:

-	if len(stack) > 0 {
-		return false
-	}
-	return true
+	return len(stack) == 0

Additionally, consider using rune directly instead of repeated string(val) conversions for minor performance improvement:

 func IsValidParentheses(s string) bool {
-	parenthesesMap := map[string]string{
-		")": "(",
-		"}": "{",
-		"]": "[",
+	parenthesesMap := map[rune]rune{
+		')': '(',
+		'}': '{',
+		']': '[',
 	}
-	var stack []string
+	var stack []rune
 	for _, val := range s {
 		stackLen := len(stack)
-		value, ok := parenthesesMap[string(val)]
+		value, ok := parenthesesMap[val]
 		if ok && stackLen > 0 && value == stack[stackLen-1] {
 			stack = stack[:stackLen-1]
 		} else {
-			stack = append(stack, string(val))
+			stack = append(stack, val)
 		}
 	}
-
-	if len(stack) > 0 {
-		return false
-	}
-	return true
+	return len(stack) == 0
 }

📜 Review details

Configuration used: CodeRabbit UI

Review profile: CHILL

Plan: Pro

📥 Commits

Reviewing files that changed from the base of the PR and between 475fab4 and 3f822b6.

📒 Files selected for processing (3)

• Go/leetcode.go (6 hunks)
• Go/leetcode_test.go (1 hunks)
• Go/main.go (1 hunks)

🧰 Additional context used

🧬 Code graph analysis (2)

Go/main.go (1)

Go/leetcode.go (1)

• IsValidParentheses (220-241)

Go/leetcode_test.go (1)

Go/leetcode.go (1)

• IsValidParentheses (220-241)

🔇 Additional comments (2)

Go/main.go (1)

9-10: LGTM!

The demo call correctly tests the new IsValidParentheses function with an invalid input that should return false, demonstrating the validation logic.

Go/leetcode_test.go (1)

154-174: No duplicate functions detected—AI summary was incorrect.

Verification confirms only one Test_ValidParentheses function exists at line 154. The code compiles without duplicate-related errors. The test cases are comprehensive and correct, covering valid parentheses, mismatched brackets, and incorrect nesting patterns.