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.

代码

/** * Definition for binary tree * public class TreeNode { *     int val; *     TreeNode left; *     TreeNode right; *     TreeNode(int x) { val = x; } * } */public class Solution {    List
     
       deep_list=new ArrayList
      
       ();    public int maxDepth(TreeNode root) {        if(root==null) return 0;        getDepth(root,1);        int max=1;        for(int i=0;i
       
        max){                max=deep_list.get(i);            }                    }        return max;    }    public void getDepth(TreeNode root,int height){        if(root==null)          {            deep_list.add(height-1) ;            return;        }        getDepth(root.left,height+1);        getDepth(root.right,height+1);    }}