构造排序二叉树，并按行从左到右输出

import java.util.LinkedList;
import java.util.Queue;

public class Main {
    class BinaryNode {
        int val;
        BinaryNode left;
        BinaryNode right;

        public BinaryNode(int val) {
            this.val = val;
        }
    }//BinaryNode

    private BinaryNode root;//根节点,这个属性很重要

    private void buildOrderTree(int[] vals) {
        for (int i = 0; i < vals.length; i++) {
            insert(vals[i]);
        }
    }//build

    private void insert(int val) {
        root = insert(root, val);
    }//insert

    private BinaryNode insert(BinaryNode root, int val) {
        if (root == null)