パナソニックグループプログラミングコンテスト2023(AtCoder Beginner Contest 301)
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Problem Statement

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There are $N$ people in a three-dimensional space. The $i$-th person is at the coordinates $(X_i,Y_i,Z_i)$. All people are at different coordinates, and we have $X_i>0$ for every $i$.

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You will choose a point $p=(x,y,z)$ such that $x<0$, and take a photo in the positive $x$-direction.

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If the point $p$ and the positions $A, B$ of two people are on the same line in the order $p,A,B$, then the person at $B$ will not be in the photo. There are no other potential obstacles.

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Find the number of people in the photo when $p$ is chosen to minimize this number.

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Constraints

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  • $1 \leq N \leq 50$
  • $0 < X_i \leq 1000$
  • $-1000 \leq Y_i,Z_i \leq 1000$
  • The triples $(X_i,Y_i,Z_i)$ are distinct.
  • All values in the input are integers.
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Input

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The input is given from Standard Input in the following format:

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N
X_1 Y_1 Z_1
\vdots
X_N Y_N Z_N

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Output

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Print the answer.

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样例

Input #1
3
1 1 1
2 2 2
100 99 98
Output #1
2
For instance, if you take the photo from the point $(-0.5,-0.5,-0.5)$, it will not show the second person.
Input #2
8
1 1 1
1 1 -1
1 -1 1
1 -1 -1
3 2 2
3 2 -2
3 -2 2
3 -2 -2
Output #2
4
If you take the photo from the point $(-1,0,0)$, it will show four people.
题目信息

题面与样例版权归 AtCoder 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。