← AlgoMindset 75

Count Good Nodes in Binary Tree

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🧠 Before you code — what pattern fits?

A node X in a binary tree is "good" if on the path from the root to X there are no nodes with a value greater than X. Return the number of good nodes.

[3,1,4,3,null,1,5] → 4

[3,3,null,4,2] → 3

🎬 Video explanation · Greg Hogg

Your solution runs against 3 unit tests, including edge and large-value cases.

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Test console · 3 unit tests

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