灵活运用非递归的遍历算法实现二叉树的其它各种运算；掌握按层次顺序遍历二叉树的方法；熟练掌握在中序线索二叉树上找给定结点的指定顺序下的前驱和后继的方法。-Flexibility in the use of non-recursive binary tree traversal algorithm to achieve a variety of other operations master-level order according to the method of binary tree tr