Maximum Level Sum of a Binary Tree — Algorithm Visualization & Coding Challenge

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Understanding Maximum Level Sum of a Binary Tree

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Problem Overview

🌳 Maximum Level Sum of a Binary Tree

Difficulty: 🟡 Medium
Topics: Binary Tree, BFS, DFS

🧠 Problem Statement

You are given the root of a binary tree.

The root is at level 1
Its children are at level 2
Their children are at level 3, and so on…

👉 Your task is to find the smallest level x such that the sum of all node values at level x is maximum.

🧪 Example 1

Input

root = [1,7,0,7,-8,null,null]

Explanation

Level	Nodes	Sum
1	1	1
2	7, 0	7
3	7, -8	-1

✅ Maximum sum = 7 at level 2

Output

🧪 Example 2

Input

root = [989,null,10250,98693,-89388,null,null,null,-32127]

Output

⚙️ Constraints

🌲 Number of nodes: 1 ≤ n ≤ 10⁴
🔢 Node value range: -10⁵ ≤ Node.val ≤ 10⁵

💡 Key Insight

Use Level Order Traversal (BFS)
Track:
- Current level
- Sum of each level
- Maximum sum seen so far
If two levels have the same sum, return the smaller level number

🚀 Tip:

Visualizing level-by-level traversal makes this problem much easier to understand. This is a perfect candidate for step-by-step tree visualization!

— Written by Saurabh Patil • B.Tech CSE • Software Developer

https://leetcode.com/problems/maximum-level-sum-of-a-binary-tree/

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Java

Output:

Understood Algorithm, Test Me now 🎮

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