题解 | #二叉树的最大深度#

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;
        }
        int leftDepth = 0;
        int rightDepth = 0;
        if (root.left != null ) {
            leftDepth = maxDepth(root.left);
        }
        if (root.right != null){
            rightDepth = maxDepth(root.right);
        }
        return (leftDepth>rightDepth?leftDepth:rightDepth)+1;
    }
}