题解 | #二叉树的最大深度#

/*
 * 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) {
        // write code here
       return dfs(root);
    }
    public int dfs(TreeNode root){
        if(root == null){
            return 0;
        }
        int h = Math.max(dfs(root.left),dfs(root.right))+1;
        return h;
    }
}