方法1:DFS(递归)
时间复杂度:$O(n)$
空间复杂度:$O(H)$
解题思路
同111题。
Java 代码
/**
* Definition for a binary tree node.
* public class TreeNode {
* int val;
* TreeNode left;
* TreeNode right;
* TreeNode() {}
* TreeNode(int val) { this.val = val; }
* TreeNode(int val, TreeNode left, TreeNode right) {
* this.val = val;
* this.left = left;
* this.right = right;
* }
* }
*/
class Solution {
public int maxDepth(TreeNode root) {
if (root == null) {
return 0;
}
int leftHeight = maxDepth(root.left);
int rightHeight = maxDepth(root.right);
return Math.max(leftHeight, rightHeight) + 1;
}
}