import java.util.*;

/*

  • public class TreeNode {
  • int val = 0;
  • TreeNode left = null;
  • TreeNode right = null;
  • } */

public class Solution { /** * * @param root TreeNode类 * @return int整型 */ public int maxDepth (TreeNode root) { if(root==null) return 0; return Math.max(maxDepth(root.left),maxDepth(root.right))+1; } }