计数题 - المسألة

#15978. 计数题

الإحصائيات

题目描述

对于 $1 \sim n$ 的错排 $p$，定义无向图 $G(p) = (V, E)$ 如下：$V = \{1, 2, \dots, n\}$，$E = \{(i, p_i) \mid 1 \le i \le n\}$。

定义无向图 $G$ 的权值 $f(G)$ 为 $G$ 中所有连通块大小的平方和。对于 $1 \sim n$ 的所有错排 $p$，求 $f(G(p))$ 之和对 $998244353$ 取模后的结果。

输入格式

一行一个正整数 $n$，表示错排长度。

输出格式

对于每组测试数据：一行一个非负整数表示答案对 $998244353$ 取模后的结果。

样例数据

样例输入

样例输出

样例解释

子任务

对于所有测试数据，满足 $2 \le n < 998244353$。

Discussions

About Discussions

The discussion section is only for posting: General Discussions (problem-solving strategies, alternative approaches), and Off-topic conversations.

This is NOT for reporting issues! If you want to report bugs or errors, please use the Issues section below.

Open Discussions 0

No discussions in this category.

Issues

About Issues

If you find any issues with the problem (statement, scoring, time/memory limits, test cases, etc.), you may submit an issue here. A problem moderator will review your issue.

Guidelines:

This is not a place to publish discussions, editorials, or requests to debug your code. Issues are only visible to you and problem moderators.
Do not submit duplicated issues.
Issues must be filed in English or Chinese only.

Active Issues 0

No issues in this category.

Closed/Resolved Issues 0