https://www.luogu.com.cn/problem/U280846

in 1 out 0，灵感：体委不能看到自己以及@Celtic 的一句“温馨提示：要特判！！！”

in 40000 out 972659433，灵感：只是想看看有无TLE。

https://www.luogu.com.cn/blog/_post/21468 https://www.luogu.com.cn/record/102126647

https://www.luogu.com.cn/blog/_post/83408 https://www.luogu.com.cn/record/102126784

https://www.luogu.com.cn/record/102126903

https://www.luogu.com.cn/blog/_post/11445 https://www.luogu.com.cn/record/102127010

https://www.luogu.com.cn/blog/_post/11446 https://www.luogu.com.cn/record/102127195

https://www.luogu.com.cn/blog/_post/11448 https://www.luogu.com.cn/record/102127222

https://www.luogu.com.cn/blog/_post/11449 https://www.luogu.com.cn/record/102127240

https://www.luogu.com.cn/blog/_post/23520 https://www.luogu.com.cn/record/102127404

https://www.luogu.com.cn/blog/_post/20548 https://www.luogu.com.cn/record/102127446

https://www.luogu.com.cn/blog/_post/157865 https://www.luogu.com.cn/record/102127679

https://www.luogu.com.cn/blog/_post/11452 https://www.luogu.com.cn/record/102127591

https://www.luogu.com.cn/blog/_post/40263 没有代码懒得补全，但没提到特判，猜测过不了。（LATEX还炸了）