QOJ.ac

QOJ

Time Limit: 1.0 s Memory Limit: 2048 MB Total points: 100

#15796. Scrambled Scrabble

統計

给定两个整数 $N$ 和 $M$。同时给定 $Q$ 个形如 $(X_j, Y_j)$ 的约束。 一个长度为 $N$ 的序列 $A = (A_1, \dots, A_N)$ 被称为“预设的”(predisposed),当且仅当:

  • 对于每个 $1 \le i \le N$,满足 $0 \le A_i < M$。
  • 对于每个 $1 \le j \le Q$,所有满足 $k$ 是 $X_j$ 的倍数的 $A_k$ 之和在模 $M$ 意义下等于 $Y_j$。形式化地,$\sum_{X_j | k} A_k \equiv Y_j \pmod M$。

求所有可能的预设序列的数量。由于答案可能非常大,请将其对 $998\,244\,353$ 取模。

输入格式

第一行包含三个整数 $N, M$ 和 $Q$ ($1 \le N, M < 998\,244\,353$; $1 \le Q \le \min(N, 100\,000)$)。 接下来的 $Q$ 行,每行包含两个整数 $X_j$ 和 $Y_j$ ($1 \le X_j \le N; 0 \le Y_j < M; X_p \neq X_q$ 当 $p \neq q$),表示一个约束。

输出格式

输出一行一个整数,表示预设序列的数量对 $998\,244\,353$ 取模的结果。

样例

输入 1

2 3 2
1 0
2 1

输出 1

1

说明 1

唯一的预设序列是 $A = (2, 1)$。

输入 2

100000 100000 1
100000 0

输出 2

373304036

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:

  1. This is not a place to publish discussions, editorials, or requests to debug your code. Issues are only visible to you and problem moderators.
  2. Do not submit duplicated issues.
  3. Issues must be filed in English or Chinese only.
Active Issues 0
No issues in this category.
Closed/Resolved Issues 0
No issues in this category.