定义线索链表类型，实现线索二叉树的基本操作。-Define the list of clues to achieve the basic operation of the two fork tree.

定义二叉链表类型，实现二叉树的基本操作：建立、先中后序遍历、层次遍历及输出。-The definition of two fork list type, two fork tree to achieve the basic operation: the establishment, the first in the order traversal, hierarchical traversal and output.