编程实现二叉树的a建立，b/c先序、中序、后序、层序遍历（递归和非递归方法），d二

叉树的高度、e繁茂度，f交换左右子树，g统计叶子节点的数目，h判断是否为完全二叉树，

i按树的形态在屏幕上打印输出。

[基本要求]

（1） 从文件中读入建树信息，树的节点数目不小于20个，树的高度不小于4。

（2） 建树信息采用两行英文字符表示，每个英文字符代表一个结点，第 1 行为树的

中序遍历结果，第 2 行为树的后序遍历结果。-Programming a binary tree establishment, b/c the first order, in order, after the order, sequence traversal (recursive and non-recursive method), the height of a binary tree d, e lush degree, f swap left and right subtrees, g statistics leaf nodes number, h to determine whether the complete binary tree, i press the shape of the tree on the screen printouts. [Basic requirements] (1) contribution　the file reads information, the number of nodes in the tree is not less than 20, the height of the tree is not less than 4. (2) The contribution of information using two lines of English character representation, each character represents a node in English, the first acts of the tree preorder result, after the first two acts of the tree preorder results.