1、 编写程序按先序次序和中序次序，确定这棵树二叉树。 2、 输出这棵树的后序序列。 (树的节点数目不超过100) -1, write a program to determine the order of the first order and sequence order tree binary tree. 2, the output of this tree postorder sequence. (The number of nodes of the tree does no