好像是n平方
by zhaolianghan @ 2024-09-20 21:12:50
好像是 $\frac{n(n-1)}{2}$
by Lieyiqi @ 2024-09-20 21:17:24
@[Lieyiqi](/user/958338) 其实就是 $\operatorname{O(n^2)}$
by Lieyiqi @ 2024-09-20 21:19:49