对二叉树的一系列操作 1.先序建立二叉树 2.中序遍历二叉树并将其线索化 3.结点前驱和后继 4.搜索二叉树 5.删除指定结点 -A series of operations on a binary tree. Preorder build binary 2 binary tree traversal and cued 3. Predecessor and successor nodes 4 5 binary search. Delete the specified no