LeetCode 199: Binary Tree Right Side View ( DFS Approach!) | lecture 12 | Tree playlist | DSA

LeetCode 199: Binary Tree Right Side View (The DFS Approach!) ​We previously solved this using BFS, but did you know you can solve it even more elegantly using Depth-First Search (DFS)? Today, we are revisiting LeetCode 199: Binary Tree Right Side View to unlock the optimal recursive solution. ​While BFS naturally processes the tree level-by-level, a modified DFS allows us to traverse the tree by prioritizing the right side first. This approach reduces our auxiliary space complexity and results in incredibly clean, concise code. ​📌 What We Will Cover: ​🔀 The Reverse DFS Pattern (Root ➡️ Right ➡️ Left): Why changing our traversal order to visit the right child before the left child changes everything. ​📏 The Level Tracking Trick: How comparing the current recursion depth to the size of our result list tells us exactly when we are seeing a level for the very first time. ​⚖️ DFS vs. BFS Space Complexity: Why DFS can be much more space-efficient (O(H) vs O(W)) on skewed trees. ​💻 Line-by-Line Code Walkthrough: Implementing the recursive solution cleanly. ​💬 Let's Compare: ​Now that you've seen both, which approach do you prefer for this problem: the iterative BFS queue or the recursive DFS? Let me know your preference and why in the comments below! ​If this video helped you master the level-tracking logic in recursion, hit that Like button and Subscribe to level up your algorithmic thinking! ​#LeetCode #BinaryTree #DepthFirstSearch #DFS #Recursion #DataStructures #Algorithms #CodingInterview #FAANG #LearnToCode