数据结构（清华第2版）中，可重用的树类，并实现对树的基本操作-Data structure (Tsinghua 2nd edition), the reusable tree class, and implement the basic operation of the tree

this tree program, i made this program for comply my daily task on class computer programing in semester 2.-this is tree program, i made this program for comply my daily task on class computer programing in semester 2.