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Binary Tree Right Side View
Learn how to solve the 'Binary Tree Right Side View' problem. This detailed resource details brute force and optimized approaches.
Problem Statement
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 tree is represented as a level-order list. Implement a function rightSideView(root: list) -> list.
Constraints
- •The number of nodes in the tree is in the range [0, 100]
- •-100 <= Node.val <= 100
Examples
Example 1
Input
[1,2,3,None,5,None,4]
Output
[1,3,4]
Explanation
From the right side: at level 0 you see 1, at level 1 you see 3, at level 2 you see 4.
Example 2
Input
[1,None,3]
Output
[1,3]
Explanation
From the right side: at level 0 you see 1, at level 1 you see 3.
Example 3
Input
[]
Output
[]
Explanation
Empty tree, nothing to see.
Need a Hint?
Perform a recursive tree traversal (DFS) or level-order traversal (BFS) using a queue/stack.
Edge Cases to Watch
- Empty list or null input variables
- Single item lists/arrays
- Extremely large input bounds causing integer or stack overflow
Ready to Solve?
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