leetcode 腾讯精选-104

题目:
https://leetcode-cn.com/problems/maximum-depth-of-binary-tree/
代码：
/**

• Definition for a binary tree node.

• struct TreeNode {

• int val;
  

• TreeNode *left;
  

• TreeNode *right;
  

• TreeNode(int x) : val(x), left(NULL), right(NULL) {}
  

• };
  /
  class Solution {
  public:
  int maxDepth(TreeNode root) {

  int num = 0;
  TreeNode *p = root;
  if(p == NULL)
  return 0;
  int num1 = maxDepth(p->left);
  int num2 = maxDepth(p->right);
  num = max(num1 ,num2) + 1;

  return num;

  }
  };

结果：