Given a binary tree, find its maximum depth.
The maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.
思路:非常基础的一个题。DFS就可以。代码例如以下:/** * Definition for a binary tree node. * public class TreeNode { * int val; * TreeNode left; * TreeNode right; * TreeNode(int x) { val = x; } * } */ public class Solution { public int maxDepth(TreeNode root) { //没有根节点 if(root == null){ return 0; } int dep1 = maxDepth(root.left); int dep2 = maxDepth(root.right); return dep1 > dep2 ? dep1+1:dep2+1; } }