The algorithm: Base case: if root is null, return Recursive case: return + max(maxDepth(left), maxDepth(right)) That's it. The recursion handles all the work. This is a post-order traversal: you compute depths of subtrees first, then combine them at the current node.
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$ curl repovive.com/roadmaps/maang-interview-prep/trees-bst/maximum-depth-of-binary-tree-solution
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