摘要: 基本恒等式 递推关系 显然有 \[\begin{aligned} \begin{bmatrix}n\\m\end{bmatrix}&=(n-1)\begin{bmatrix}n-1\\m\end{bmatrix}+\begin{bmatrix}n-1\\m-1\end{bmatrix},\\ \be 阅读全文
posted @ 2024-07-11 21:38 Gorenstein 阅读(119) 评论(0) 推荐(0)
摘要: atcoder regular ARC166: C, D.\(\quad2024/8/5\) ARC167: D, E.\(\quad2024/8/9\) ARC168: C, D.\(\quad2024/8/14\) atcoder grand AGC012: C,D,F.\(\quad2024/ 阅读全文
posted @ 2024-07-11 16:07 Gorenstein 阅读(15) 评论(0) 推荐(0)