algorythms
Tree BFS
LC #637Easy

Average of Levels in Binary Tree

Tree BFS
AmazonGoogle

Problem

Return the average value of nodes on each level of a binary tree.

treebfs

Constraints

  • 1 ≤ n ≤ 10⁴
  • -2³¹ ≤ Node.val ≤ 2³¹ − 1

Example

Inputroot = [3, 9, 20, 15, 7]
Output[3.0, 14.5, 11.0]
Why

L0 avg: 3/1=3, L1 avg: (9+20)/2=14.5, L2 avg: (15+7)/2=11

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