/** * Definition for a binary tree node. * function TreeNode(val, left, right) { * this.val = (val===undefined ? 0 : val) * this.left = (left===undefined ? null : left) * this.right = (right===undefined ? null : right) * } */ /** * @param {TreeNode} root * @return {number} */ const maxDepth = (root) => { if (null === root) return 0; return Math.max(maxDepth(root.left), maxDepth(root.right)) + 1; }; // const maxDepth = (root) => { // let depth = 0; // // const dfs = (currNode, tmpDepth) => { // if (null !== currNode) { // tmpDepth++; // dfs(currNode.left, tmpDepth); // dfs(currNode.right, tmpDepth); // } else { // depth = Math.max(depth, tmpDepth); // return; // } // } // // dfs(root, 0); // // return depth; // };