用BIT或线段树维护的神马东西，碰到这种东西智商就没有了…… 看了网上的基本所有博客，终于想明白了， 最终又看了kuangbin简单的总结： 代码： include<stdio.h> include<string.h> include<stdlib.h> include<iostream> include<algorithm> include<math.h> include<vector> include<set> include<stack> include<queue&g...