（额这种小问题也许管理直接帮忙改掉更好，题解本来就没几篇……
by MeowScore @ 2022-04-20 16:52:16
为什么要开$long long$?
by Acoipp @ 2022-08-24 10:26:14
$0 \le k,a_i \le 10^5$
by Acoipp @ 2022-08-24 10:27:22
哦，我懂了，原谅我的无知
by Acoipp @ 2022-08-24 14:15:56
数据太水，没开 $long\ long$ 随便造组数据就能卡掉。
by Remilia1023 @ 2023-02-26 04:26:52