C++实现的异质二叉树，实现了对节点的增加，删除，查询，以及整个树的释放。利用了面向对象编程的封装，继承和多态的思想。-C++ implementation of heterogeneous binary tree, the realization of the node to add, delete, query, and the release of the entire tree. Object-oriented programming using encapsulation, inher