Warning: session_start(): open(/tmp/sess_2db05f855c1dc0b6277ef01f0bec7ce2, O_RDWR) failed: No space left on device (28) in /data/wiki/inc/init.php on line 239

Warning: session_start(): Failed to read session data: files (path: ) in /data/wiki/inc/init.php on line 239

Warning: Cannot modify header information - headers already sent by (output started at /data/wiki/inc/init.php:239) in /data/wiki/inc/auth.php on line 430

Warning: Cannot modify header information - headers already sent by (output started at /data/wiki/inc/init.php:239) in /data/wiki/inc/actions.php on line 38

Warning: Cannot modify header information - headers already sent by (output started at /data/wiki/inc/init.php:239) in /data/wiki/lib/tpl/dokuwiki/main.php on line 12
2022-2023:teams:eager_to_embrace_the_seniors_thigh:c [CVBB ACM Team]

用户工具

站点工具


2022-2023:teams:eager_to_embrace_the_seniors_thigh:c

这是本文档旧的修订版!


Easy Counting Problem

题意

$1$ 到 $w$ 这 $w$ 种数每种至少在字符串中出现 $c_1, c_2, ……, c_w$ 次, $q$ 次询问,每次给出一个 $n$ ,求长度恰好为 $n$ 的字符串有多少种。

$w\le 10, q\le 300, n\le 10^7, \sum{c_i}\le 5*10^4$

题解

考虑对每种数构建指数生成函数。对于数 $i$ 显然有 $ F_i = \sum_{j \ge c_i}{\frac{x^j}{j!}} $ 。

2022-2023/teams/eager_to_embrace_the_seniors_thigh/c.1659853195.txt.gz · 最后更改: 2022/08/07 14:19 由 11231123