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warmup10 min

Maximum Depth of Binary Tree

Maximum Depth of Binary Tree

Given the root of a binary tree ({ val, left, right }, null for a missing child), return its maximum depth — the number of nodes along the longest path from root to a leaf. The simplest recursive definition: a tree's depth is 1 + max(depth(left), depth(right)), with an empty tree having depth 0.

maxDepth(tree([3, 9, 20, null, null, 15, 7])); // 3

Run your code to see results.

Stuck? This challenge exercises:

javascript.data-structures