Codeforces Round 409 (rated, Div. 2, based on VK Cup 2017 Round 2)
D
Volatile Kite
Codeforces
未评级
原题
← CE →
翻译中…

You are given a convex polygon $*P*$ with $*n*$ distinct vertices $*p*_{1}, *p*_{2}, ..., *p*_{*n*}$. Vertex $*p*_{*i*}$ has coordinates $(*x*_{*i*}, *y*_{*i*})$ in the 2D plane. These vertices are listed in clockwise order.

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You can choose a real number $*D*$ and move each vertex of the polygon a distance of at most $*D*$ from their original positions.

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Find the maximum value of $*D*$ such that no matter how you move the vertices, the polygon does not intersect itself and stays convex.

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Input

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The first line has one integer $*n*$ ($4 ≤ *n* ≤ 1 000$) — the number of vertices.

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The next $*n*$ lines contain the coordinates of the vertices. Line $*i*$ contains two integers $*x*_{*i*}$ and $*y*_{*i*}$ ($- 10^{9} ≤ *x*_{*i*}, *y*_{*i*} ≤ 10^{9}$) — the coordinates of the $*i*$-th vertex. These points are guaranteed to be given in clockwise order, and will form a strictly convex polygon (in particular, no three consecutive points lie on the same straight line).

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Output

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Print one real number $*D*$, which is the maximum real number such that no matter how you move the vertices, the polygon stays convex.

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Your answer will be considered correct if its absolute or relative error does not exceed $10^{ - 6}$.

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Namely, let's assume that your answer is $*a*$ and the answer of the jury is $*b*$. The checker program will consider your answer correct if image.

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Note

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Here is a picture of the first sample

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image

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Here is an example of making the polygon non-convex.

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image

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This is not an optimal solution, since the maximum distance we moved one point is $≈ 0.4242640687$, whereas we can make it non-convex by only moving each point a distance of at most $≈ 0.3535533906$.

翻译中…

样例

Input #1
4
0 0
0 1
1 1
1 0
Output #1
0.3535533906
InputCopy OutputCopy
Input #2
6
5 0
10 0
12 -4
10 -8
5 -8
3 -4
Output #2
1.0000000000
InputCopy OutputCopy
题目信息
题号
801D
时间限制
2 s
内存限制
256 MB

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。