Is Binary Tree Right Side View easy or hard?

Binary Tree Right Side View is considered a Medium difficulty problem. The logic is straightforward once you recognize the level-order or right-first traversal pattern, but it requires understanding of tree traversal and careful handling of levels or recursion depth.

How to solve Binary Tree Right Side View in O(n)?

Traverse the tree once using either BFS or DFS. In BFS, iterate through each level using a queue and record the last node encountered in that level. In DFS, traverse the right subtree before the left and record the first node seen at each depth. Both approaches ensure each node is processed once, giving O(n) time complexity.

Binary Tree Right Side View Python or Java solution

Python and Java solutions typically use a queue for BFS or recursion for DFS. The BFS implementation iterates through each level and stores the last node value in the result list. The DFS implementation traverses right before left and records the first node encountered at each depth.

What is the best approach for Binary Tree Right Side View?

Both BFS level-order traversal and DFS right-first traversal solve the problem efficiently in O(n) time. BFS is often considered the most intuitive because you process nodes level by level and record the last node in each level. DFS is equally optimal and records the first node encountered at each depth when traversing right before left.

What data structure is used in Binary Tree Right Side View?

The main data structures used are queues and recursion stacks. BFS uses a queue to process nodes level by level, while DFS relies on the recursion call stack to track traversal depth. Both approaches operate on a binary tree structure.

What is the time complexity of Binary Tree Right Side View?

The optimal time complexity is O(n) because every node in the binary tree is visited exactly once. BFS processes nodes level by level using a queue, while DFS visits each node recursively. Space complexity is O(n) for BFS and O(h) for DFS where h is the tree height.

Is Binary Tree Right Side View asked at Google, Amazon, or Meta?

Binary Tree Right Side View is a common tree traversal interview problem and has appeared in interview prep lists associated with companies like Amazon, Google, and Meta. It tests understanding of BFS level traversal, DFS recursion, and tree visibility logic.

Description Solution Video 10:16

199. Binary Tree Right Side View

Medium71.5% acceptance14 companies

Given the root of a binary tree, imagine yourself standing on the right side of it, return the values of the nodes you can see ordered from top to bottom.

Example 1:

Input: root = [1,2,3,null,5,null,4]

Output: [1,3,4]

Explanation: