英语语法分析

You can preorder a name before it drops and hope to get it.

当你希望拿到一个删除的域名时，你能预订到。

How does the recursion preorder traversal algorithm go back to parent?

前序遍历的递归算法如何回到父母吗？

Given preorder and inorder traversal of a tree, construct the binary tree.

给定一个二叉树的前序和中序遍历，重建这棵二叉树。