树的水平输出算法实现：对于给定二叉树，以水平方向输出二叉树。每个节点包含一个整数值，并且节点数最大255。节点数据的输出方向为从左到右，从上到下，同一水平高度的节点输出完成后，再输出下一水平高度。

-The tree level output algorithm: output in the horizontal direction for a given binary tree, binary tree. Each node contains an integer value, and the number of nodes 255. The direction of the output of the node data from left to right, top to bottom, after the completion of the same height of the node output, then output the height of the next level.