二叉树结构的定义，并对所定义的树结构进行遍历-failed to translate

HUffman的算法，包括以索引的方式树形输出-HUffman algorithms, including the way the index tree output

这是关于二叉树遍历的程序，包括前序、中序、后序，以及递归和非递归遍历-This is about the binary tree traversal procedures, including pre-order, in order, the order, as well as non-recursive and recursive traversal