@[小粉兔](/user/10703)
by tommy0221 @ 2020-11-23 14:17:52
@[世外明月](/user/123384) fixed
by 小粉兔 @ 2020-11-23 14:24:04
@[tommy0221](/user/123384) a和b是表示下标,原题的意思是x1,xn可以无限选,但是一个序列只能有一个,所以没问题吧
by leader_one @ 2021-01-30 20:54:39
@[小粉兔](/user/10703)
by leader_one @ 2021-01-30 20:55:01
@[leader_one](/user/75343) fixed
by 小粉兔 @ 2021-01-31 00:27:35