常用树数据结构集合，包括二叉树、二叉查找树、AA树、红黑树、伸展树的一整套实现，自带包装器、异常处理类，方便使用-common pool tree data structure, including the binary tree, binary search tree, AA tree, a red, black tree extend to achieve a set of trees, bringing their wrapper, abnormal class, user-friendl