Public Judge

pjudge

Time Limit: 4.5 s Memory Limit: 2048 MB Total points: 100
Statistics

有 $m$ 个球,编号为 $1\sim m$,每个球为黑色或白色。一开始,所有的球为白色。

接下来,你要做 $n$ 次操作,每次操作形如:将一个球的颜色翻转(从黑染白,或从白染黑)。

你还需要保证,在第 $i$ 次操作结束后,只有编号 $\le a_i$ 的球可能为黑色,编号 $> a_i$ 的球必须为白色。

你要求出有多少种不同的合法操作的方案,对 $998244353$ 取模。两种操作方案不同当且仅当在某次操作中,选中球的编号不同。

但是这还不够,你要处理 $q$ 次修改,每次修改形如:将 $a_{x_i}$ 改为 $y_i$,然后求出当前 $a$ 对应的答案。

输入格式

第一行输入 $n,m,q$。

第二行 $n$ 个整数,表示 $a_i$。

接下来 $q$ 行,每行两个数 $x_i,y_i$。

输出格式

输出 $q$ 行,每行一个答案。

样例输入 1

3 3 2
1 3 1
3 2
1 3

样例输出 1

5
14

样例输入 2

6 8 1
3 8 7 7 1 6
1 4

样例输出 2

2100

样例输入 3

12 10 8
1 3 2 6 3 6 7 7 5 5 4 7
12 4
7 10
4 2
9 8
9 9
8 3
4 9
10 2

样例输出 3

2741280
3007680
1503840
1916160
1972800
728640
1821600
621440

样例输入/输出 4~6

见下发文件。

数据范围

对于所有数据,$n,q\le 3\times 10^4,m\le 15,1\le a_i,y_i\le m,1\le x_i\le n$。

各子任务的附加限制如下表所示:

子任务编号 $n\le$ $m\le$ $q\le$ 得分
$1$ $5$ $5$ $10$ $4$
$2$ $2000$ $10$ $1$ $6$
$3$ $30000$ $10$ $1$ $8$
$4$ $30000$ $15$ $1$ $24$
$5$ $30000$ $15$ $10$ $12$
$6$ $30000$ $7$ $30000$ $14$
$7$ $30000$ $10$ $30000$ $16$
$8$ $30000$ $15$ $30000$ $16$

Discussions

About Discussions

The discussion section is only for posting: Editorials, 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. Submitting multiple issues may cause your account to be banned.
  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.