Add: [n-queens] in [c++]

[JitinSaxenaa]

📌 Summary
This PR adds a comprehensive implementation of the N-Queens Problem in C++ to enhance the repository’s backtracking algorithms collection.

🚀 What's Added

• File: CPP/algorithms/backtracking/n_queens.cpp
• Complete N-Queens implementation using recursive backtracking
• Well-documented code with detailed comments
• Example usage and test cases included

📊 Algorithm Details

• Time Complexity: O(N!) (worst-case due to permutations)
• Space Complexity: O(N²) for board representation
• Algorithm Type: Backtracking / Constraint Satisfaction Problem

✨ Key Features
✅ Clear function documentation
✅ Step-by-step implementation comments
✅ Example output demonstration (all possible solutions)
✅ Test cases covering multiple board sizes
✅ Follows repository naming conventions (snake_case)

🧪 Testing
The implementation includes test cases for:

• N = 1 (trivial case)
• N = 4 (first non-trivial valid case)
• N = 8 (classic chessboard scenario)
• Larger values of N for performance testing

📚 Code Quality

• Clean, readable code structure
• Comprehensive inline comments
• Proper function separation (isSafe, solveNQueens, utility functions)
• Example usage in main function

🎯 Contribution Type

• Algorithm Implementation
• Documentation
• Code Examples
• Following contribution guidelines

[github-actions]

🎉 Welcome to Hacktoberfest 2025, @JitinSaxenaa! 🎃

Thank you for your first contribution to our DSA repository! Here's what happens next:

🔍 Automatic Checks

• ✅ Code Validation: Passed
• 🧪 Compilation Tests: Passed

📋 Next Steps

🎯 Great job! Your code compiled successfully. Maintainers @Karanjot786 and @Pradeepsingh61 will review your PR soon.

🎁 What You Get

• 🏆 Hacktoberfest Credit: This PR counts toward your 6 PR goal for exclusive T-shirt + Tree!
• 🌟 Hall of Fame: You'll be featured in our contributors list
• 📚 Learning: Code review feedback from experienced developers

💡 Tips for Success

• Follow our Contributing Guidelines
• Add comments explaining your algorithm
• Include time/space complexity analysis
• Test your code before submitting

Welcome to the community! 🚀

[github-actions]

🤖 Automated PR Status

🔍 Code Validation

✅ Passed - File naming and structure look good!

🧪 Compilation Tests

✅ Passed - All code compiles successfully!

📋 Overall Status

🎉 Ready for Review - Your PR has passed all automated checks!
👥 Maintainers have been notified for review.

---

This comment was generated automatically. Checks will re-run when you push new commits.

[Karanjot786]

Hi @JitinSaxenaa, can you change the directory of this file like this one CPP/algorithms/recursion/n_queen_problem.cpp

[github-actions]

🎉 Welcome to Hacktoberfest 2025, @JitinSaxenaa! 🎃

Thank you for your first contribution to our DSA repository! Here's what happens next:

🔍 Automatic Checks

• ✅ Code Validation: Passed
• 🧪 Compilation Tests: Failed

📋 Next Steps

⚠️ Action needed: Please fix the compilation errors and push your changes.

🎁 What You Get

• 🏆 Hacktoberfest Credit: This PR counts toward your 6 PR goal for exclusive T-shirt + Tree!
• 🌟 Hall of Fame: You'll be featured in our contributors list
• 📚 Learning: Code review feedback from experienced developers

💡 Tips for Success

• Follow our Contributing Guidelines
• Add comments explaining your algorithm
• Include time/space complexity analysis
• Test your code before submitting

Welcome to the community! 🚀

[github-actions]

🤖 Automated PR Status

🔍 Code Validation

✅ Passed - File naming and structure look good!

🧪 Compilation Tests

❌ Failed - Please fix compilation errors and try again.

📋 Overall Status

⚠️ Needs Work - Please address the issues above.
💡 Push new commits to automatically re-run these checks.

---

This comment was generated automatically. Checks will re-run when you push new commits.

[github-actions]

🎉 Welcome to Hacktoberfest 2025, @JitinSaxenaa! 🎃

Thank you for your first contribution to our DSA repository! Here's what happens next:

🔍 Automatic Checks

• ✅ Code Validation: Passed
• 🧪 Compilation Tests: Passed

📋 Next Steps

🎯 Great job! Your code compiled successfully. Maintainers @Karanjot786 and @Pradeepsingh61 will review your PR soon.

🎁 What You Get

• 🏆 Hacktoberfest Credit: This PR counts toward your 6 PR goal for exclusive T-shirt + Tree!
• 🌟 Hall of Fame: You'll be featured in our contributors list
• 📚 Learning: Code review feedback from experienced developers

💡 Tips for Success

• Follow our Contributing Guidelines
• Add comments explaining your algorithm
• Include time/space complexity analysis
• Test your code before submitting

Welcome to the community! 🚀

[github-actions]

🤖 Automated PR Status

🔍 Code Validation

✅ Passed - File naming and structure look good!

🧪 Compilation Tests

✅ Passed - All code compiles successfully!

📋 Overall Status

🎉 Ready for Review - Your PR has passed all automated checks!
👥 Maintainers have been notified for review.

---

This comment was generated automatically. Checks will re-run when you push new commits.

[github-actions]

🎉 Welcome to Hacktoberfest 2025, @JitinSaxenaa! 🎃

Thank you for your first contribution to our DSA repository! Here's what happens next:

🔍 Automatic Checks

• ✅ Code Validation: Passed
• 🧪 Compilation Tests: Passed

📋 Next Steps

🎯 Great job! Your code compiled successfully. Maintainers @Karanjot786 and @Pradeepsingh61 will review your PR soon.

🎁 What You Get

• 🏆 Hacktoberfest Credit: This PR counts toward your 6 PR goal for exclusive T-shirt + Tree!
• 🌟 Hall of Fame: You'll be featured in our contributors list
• 📚 Learning: Code review feedback from experienced developers

💡 Tips for Success

• Follow our Contributing Guidelines
• Add comments explaining your algorithm
• Include time/space complexity analysis
• Test your code before submitting

Welcome to the community! 🚀

[github-actions]

🤖 Automated PR Status

🔍 Code Validation

✅ Passed - File naming and structure look good!

🧪 Compilation Tests

✅ Passed - All code compiles successfully!

📋 Overall Status

🎉 Ready for Review - Your PR has passed all automated checks!
👥 Maintainers have been notified for review.

---

This comment was generated automatically. Checks will re-run when you push new commits.