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
        //递归
        if(root==null) return 0;
        return 1+Math.max(maxDepth(root.left),maxDepth(root.right));
    }
}