In mathematics you don't understand things, you just get used to them.

DescriptionLink。给出一个二维平面以及一些点,保证点不在同行 / 同列。每次询问求出一个子矩阵里面的顺序对。Solution卡常,卡你吗。膜拜 dX。基本是把 dX 的题解贺了过来...