Codeforces Round 773 (Div. 2)
A
Hard Way
Codeforces
800
原题
←B →
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Sam lives in Awesomeburg, its downtown has a triangular shape. Also, the following is true about the triangle:

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  • its vertices have integer coordinates,
  • the coordinates of vertices are non-negative, and
  • its vertices are not on a single line.
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He calls a point on the downtown's border (that is the border of the triangle) safe if he can reach this point from at least one point of the line $y = 0$ walking along some straight line, without crossing the interior of the triangle.

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image In the picture the downtown is marked with grey color. The first path is invalid because it does not go along a straight line. The second path is invalid because it intersects with the interior of the downtown. The third and fourth paths are correct.

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Find the total length of the unsafe parts of the downtown border. It can be proven that these parts are segments and their number is finite.

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Input

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Each test contains multiple test cases. The first line contains a single integer $t$ ($1 \le t \le 1000$) — the number of test cases. Description of the test cases follows.

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Each test case contains three lines, each of them contains two integers $x_i$, $y_i$ ($0 \le x_i, y_i \le 10^9$) — coordinates of the vertices of the downtown's border.

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Output

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For each test case print a single number — the answer to the problem.

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Your answer will be considered correct if its absolute or relative error does not exceed $10^{-9}$. Formally let your answer be $a$, jury answer be $b$. Your answer will be considered correct if $\frac{|a - b|}{\max{(1, |b|)}} \le 10^{-9}$.

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Note

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In the picture, the downtowns of the first three test cases are illustrated. Triangles are enumerated according to the indices of test cases they belong to.

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image

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In the first two test cases, all points on the borders of the downtowns are safe, thus the answers are $0$.

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In the following picture unsafe points for the third test case are marked with black color:

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image

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In the fourth test case, all points on the border of the downtown are safe.

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样例

Input #1
5
8 10
10 4
6 2
4 6
0 1
4 2
14 1
11 2
13 2
0 0
4 0
2 4
0 1
1 1
0 0
Output #1
0.0000000
0
2.0000
0.00
1
InputCopy OutputCopy
题目信息
题号
1642A
时间限制
1 s
内存限制
256 MB
标签
计算几何

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。