本来就是啊，，这是noip的题目你还想怎样、、
by Sai0511 @ 2018-10-06 14:20:51
众所周知，$n^2$是可以过$10^6$的 $\ \ \ \ \ \ $(逃
by da32s1da @ 2018-10-06 14:20:58
@[da32s1da](/space/show?uid=50092)
~~n方过百万，暴力碾标算~~
by RiverFun @ 2018-10-06 14:35:40