摘要: Trial Round: Rectangles \[ans=\sum_{1\leq i\leq j\leq n}[ij\leq n]=\frac{\lfloor\sqrt{n}\rfloor+\sum_{1\leq i,j\leq n}[ij\leq n]}{2}=\frac{\lfloor\sqr 阅读全文
posted @ 2022-01-25 21:38 Claris 阅读(297) 评论(0) 推荐(1) 编辑