LeetCode 1161: Maximum Level Sum of a Binary Tree | CSharp Solution | BFS Traversal

In this video, I solve LeetCode problem 1161, finding the level with maximum sum in a binary tree using #bfs traversal. We'll implement a clean, efficient C# solution with Queue-based level order traversal. ⏱️ **Time Complexity**: O(n) where n is the number of nodes 🧠 **Space Complexity**: O(w) where w is the maximum width of the tree ## ⏰ Timestamps 00:00 - Understanding problem statement 00:46 - Using BFS 03:12 - Big O Notation calculated 03:41 - C# ode walk-through 04:38 - Solution analysis - runtime + memory 04:46 - Conclusion ## 🔑 Key Concepts - Binary Tree Traversal - Level Order Traversal (BFS) - Queue-based implementation - #datastructures #binarytree #breadthfirstsearch ## 📚 Learning Points - How to perform level-aware BFS traversal - Tracking level information during tree traversal - Efficient ways to calculate sums per level - Handling edge cases like empty trees ## 🔄 Related Problems - 102: Binary Tree Level Order Traversal - 637: Average of Levels in Binary Tree - 515: Find Largest Value in Each Tree Row - 107: Binary Tree Level Order Traversal II ## 👥 Target Audience This video is perfect for software engineers preparing for coding interviews, computer science students learning tree algorithms, and developers looking to improve their problem-solving skills with binary trees. ## 📋 Prerequisites - Basic understanding of binary trees - Familiarity with breadth-first search - C# programming knowledge - Understanding of queue data structure ## 🔗 Links - LeetCode problem: https://leetcode.com/problems/maximum-level-sum-of-a-binary-tree/ - Solution code: ## 💡 Additional Tips - Pay attention to the level numbering (1-indexed in the problem vs. 0-indexed in code) - Consider using a dictionary to store level sums for very large trees - Watch for integer overflow with large input values ## 🔔 Call to Action If you found this explanation helpful, please subscribe to my channel for more coding interview preparation videos! Drop your questions or alternative approaches in the comments below. Let me know what LeetCode problems you'd like me to cover next! #leetcode #coding #interviews #csharp