Vladik had started reading a complicated book about algorithms containing n pages. To improve understanding of what is written, his friends advised him to read pages in some order given by permu

由题意，我们可以建立一个二叉树。 然后中序遍历二叉树，得到最终的结果。 在中序遍历二叉树的时候，我们判断当前子树的根节点与其子节点的符号之间的关系。 #include<stdio.h>#include<string.h>#include<iostream>#include<algorithm>#include<vector>#include<stack>#define LL