Leetcode•May 15, 2025
Maximum Depth of Binary Tree
Hazrat Ali
Leetcode
A binary tree's maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.
Example 1:
Input: root = [3,9,20,null,null,15,7] Output: 3
Example 2:
Input: root = [1,null,2] Output: 2
Solution
/**
* @param {TreeNode} root
* @return {number}
*/
const maxDepth = root => {
if (!root) {
return 0;
}
return 1 + Math.max(maxDepth(root.left), maxDepth(root.right));
};