Medium · Trees

Count Good Nodes in Binary Tree

Given the root of a non-empty binary tree, return the number of good nodes. A node is good if no node on the path from the root to it has a value greater than its own.

Examples

Example 1

[3,1,4,3,null,1,5]

Output: 4 good nodes

Example 2

[3,3,null,4,2]

Output: 3 good nodes

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