Breadth-First Search/Binary Tree Right Side ViewMedium

This practice workspace is built for desktop. Open it on a larger screen to start solving.

Binary Tree Right Side View

Breadth-First Search·Medium

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.

The visible node at each level is the rightmost node at that level — but if the rightmost slot is empty, fall through to whichever node is actually rightmost. For a left-skewed tree, every node is visible because each level has only one node.

Input convention. Level-order array with null for missing children. The starter includes TreeNode and arrayToTree. BFS is the natural fit.

Examples

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

Output: [1,3,4]

Input: values = [1,null,3]

Output: [1,3]

Input: values = []

Output: []

Constraints

The number of nodes is in the range [0, 100].
-100 <= Node.val <= 100

00:00Preview Mode (Read Only)

Loading editor…

Tests

Preview Mode

This is a read-only preview of DSAMind's AI coaching. Sign up to get custom feedback on your own solution.

Passed32 ms

First attempt — retry to track metric movement here.

Your approach

Pattern:Breadth-First Search
Time:O(N)
Space:O(1)

Complete approach — pattern and complexity both named.

Coach

What you got right

You correctly matched the sorted input requirement and implemented a linear-time scan using two pointers.

Where it diverged

No divergence detected. The code correctly aligns with the stated approach.

Next attempt: focus on

Try solving related sliding window problems to build familiarity with two-pointer variants.

Signals

No signals fired — clean run, you stayed in flow.