using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        //for the given array of points the result should be 2

        var result = new Solution().solution(new Point2D[] {

            new Point2D { x = -1, y = -2 },

            new Point2D { x = 1, y = 2 },

            new Point2D { x = 2, y = 4 },

        });

        Console.WriteLine(result);

    }

}

​

public class Solution

{

    //do not change the method signature

    public int solution(Point2D[] A)

    {

        var hash = new HashSet<double>();

​

        foreach (var point in A)

            hash.Add(point.x / point.y);

​

        return hash.Count;

    }

}

​

public class Point2D

{

    public long x;

    public long y;

}