`x-=2`应该放在`for`循环的外面，实测有效。
by AmaZingFantasy @ 2021-07-31 13:20:16
要不然每输出一个数字 $x$ 都要减 $2$。
by AmaZingFantasy @ 2021-07-31 13:21:09
@[ZHUYIHAN](/user/509176)
by AmaZingFantasy @ 2021-07-31 13:21:27
@[安湛丰](/user/378220)
谢谢
by ZHUYIHAN @ 2021-08-01 08:20:42