QOJ.ac

QOJ

Limite de temps : 1.5 s Limite de mémoire : 256 MB Points totaux : 100 Hackable ✓

#12923. 凸包

Statistiques

三维空间中有 $n$ 个点。考虑这 $n$ 个点的凸包。 给定 $q$ 次询问。每次询问定义一个三维空间中的平面。对于每个给定的平面,求该平面与凸包截面的面积。

第一行包含两个整数 $n$ 和 $q$,分别表示点的数量和询问的数量 ($1 \le n, q \le 1000$)。

接下来 $n$ 行,每行包含三个整数 $x, y, z$,表示其中一个点的坐标。

接下来 $q$ 行描述询问。每行包含四个整数 $a, b, c, d$,表示由方程 $ax + by + cz + d = 0$ 定义的平面。

保证 $x, y, z, a, b, c, d$ 的绝对值均不超过 $2000$。

对于每次询问,输出答案,要求绝对误差不超过 $10^{-3}$。

样例

输入格式 1

6 1
0 0 1
1 0 1
0 1 1
0 0 -1
1 0 -1
0 1 -1
0 0 1 0

输出格式 1

0.500

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.