将二叉搜索树变为双向链表，先序遍历输入节点，输出双向链表-The binary search tree into a doubly linked list, doubly linked list of the preorder traversal of the input node, output

二叉树的建立 中序遍历二叉树 把二叉树转换成双向链表-Binary tree in the establishment of traversing Binary conversion to binary tree into a doubly linked list

用二叉链表存储二叉树，用“扩张先序遍历序列”创建二叉链表，对二叉树进行前、中、后序的遍历以及层次遍历，输出度为0、1、2的节点及节点数，线索化二叉树，根据线索化的二叉树查找二叉树中任意节点的前驱、后继，通过线索二叉树进行二叉树节点的删除、插入，以及按树状打印二叉树。-Used to store binary tree binary tree, use the " expansion preorder sequence" to create the binary tree, th