这是我自己编写的，关于多路树查找－外部查找(B树)【源代码】-This is what I have written, and on the multi-tree search- Find External (B tree) 【Source】

B树功能的基本实现（B树的插入，查找，删除等）。只有基本构造。不能执行-The basic function of the B-tree implementation (B tree insertion, search, delete, etc.). Only basic structure. Can not be executed