QOJ.ac

QOJ

Time Limit: 1 s Memory Limit: 1024 MB Total points: 100

#3732. 最长上升子序列

الإحصائيات

Bobo 在 ICPCCamp 学会了解决最长上升子序列问题后得到了一个长度为 $n$ 的数列 $p_1, p_2, \dots, p_n$.

Bobo 想用 $1, 2, \dots, n$ 来替换其中值为 $0$ 的元素,使得 $p_1, p_2, \dots, p_n$ 互不相同(即 $p_1, p_2, \dots, p_n$ 是 $\{1, 2, \dots, n\}$ 的排列)。

现在 Bobo 想知道,替换后最长上升子序列的长度恰好为 $(n - 1)$ 数列的数量。

输入

输入包含不超过 $300$ 组数据,其中不超过 $20$ 组的 $n$ 超过 $100$.

每组数据的第一行包含一个整数 $n$ ($1 \leq n \leq 10^5$).

第二行包含 $n$ 个整数 $p_1, p_2, \dots, p_n$ ($0 \leq p_i \leq n$).

保证 $p_1, p_2, \dots, p_n$ 中非 $0$ 的元素互不相同。

输出

对于每组数据,输出一个整数表示要求的值。

样例输入

3
0 0 0
4
0 0 0 0
5
1 0 0 4 5

样例输出

4
9
1
About Issues

We understand that our problem archive is not perfect. If you find any issues with the problem, including the statement, scoring configuration, time/memory limits, test cases, etc.

You may use this form to submit an issue regarding the problem. A problem moderator will review your issue and proceed it properly.

STOP! Before you submit an issue, please READ the following guidelines:

  1. This is not a place to publish a discussion, editorial, or requests to debug your code. Your issue will only be visible by you and problem moderators. Other users will not be able to view or reply your issues.
  2. Do not submit duplicated issues. If you have already submitted one, please wait for an moderator to review it. Submitting multiple issues will not speed up the review process and might cause your account to be banned.
  3. Issues must be filed in English or Chinese only.
  4. Be sure your issue is related to this problem. If you need to submit an issue regarding another problem, contest, category, etc., you should submit it to the corresponding page.

Active Issues 0

No issues in this category.

Closed/Resolved Issues 0

No issues in this category.