#P3897. [湖南集训] Crazy Rabbit
[湖南集训] Crazy Rabbit
Description
The rabbits decide to station some soldiers in their castle.
Given the coordinates of points and a circular obstacle in the castle whose center is at the origin, the rabbits want to choose rabbits such that, for every pair of chosen rabbits, the line determined by them does not intersect the circle.
The rabbits want to know the maximum number of rabbits they can choose.
Input Format
The first line contains two integers and , denoting the number of rabbits and the radius of the circle.
Then lines follow. Each line contains two integers and , representing the coordinates of the -th rabbit.
It is guaranteed that every rabbit lies strictly outside the obstacle, and that for any two rabbits, the line through them is not tangent to the circle.
Output Format
Output a single integer on one line, representing the maximum number of rabbits that can be chosen.
6 3
0 6
-7 -4
-3 -2
7 -5
-2 3
8 -3
4
Hint
Sample 1 Explanation

Choosing rabbits works.
Constraints
- For of the testdata, .
- For of the testdata, .
- For of the testdata, and .
Translated by ChatGPT 5
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