数据结构经典实例，深入了解二叉树。如：可查询每个节点的层次，从根到该节点的枝长（路径长度），子孙的个数及祖先的个数。每个节点在前序、中序、后序中的访问的序号。-Classic examples of data structures, in-depth understanding of binary tree. Such as: to check the level of each node, the node from the root to shoot length (path length), the number of offspring and the number of ancestors. Each node of the first order, in order, the order of the access number.