Question

题目内容

解题思路

dfs + 递归。

代码实现

/**
 * Definition for a binary tree node.
 * class TreeNode {
 *     val: number
 *     left: TreeNode | null
 *     right: TreeNode | null
 *     constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {
 *         this.val = (val===undefined ? 0 : val)
 *         this.left = (left===undefined ? null : left)
 *         this.right = (right===undefined ? null : right)
 *     }
 * }
 */

const maxDepth = (root: TreeNode | null): number => {
  if (root === null) return 0;
  let leftDepth = maxDepth(root?.left);
  let rightDepth = maxDepth(root?.right);
  return Math.max(leftDepth, rightDepth) + 1;
};