```else ans=(ans+sum+n)%n```
膜后的值域是 0 - $n$，不是 1 - $n$
by Missa @ 2022-03-17 18:16:37
0 - n-1
by Missa @ 2022-03-17 18:16:58
@[Missa](/user/443664) 谢谢大佬！
by charleshe @ 2022-03-19 12:21:06