说明：  首先，实现二叉树的创建和中序递归遍历算法，在此基础上，进一步实现二叉树的其它递归遍历算法和横向打印算法，最后再增加二叉树的非递归遍历算法、删除子树等算法。
(First of all, the realization of the binary tree in order to create and recursive traversal algorithm, On this basis, the further the other recursive binary tree traversal algorithm and horizontal printing algorithm, binary tree and then increase over the non-recursive calendar algorithms, such as the deletion of sub-tree algorithm.)