1. 

package acm_11227_the_silver_bullet;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.Scanner;

/**
 * FWP, AusgewŠhlte Probleme aus dem ACM Programming Contest, WS10 
 * Problem: acm_11227_the_silver_bullet
 * Link: 
 * 
 * @author Martin Lambeck
 * @version 1.0, 23.10.2010
 * 
 * Method : adhoc
 * Status : Accepted
 * Runtime: 0.600
 */


public class Main
{
	static Scanner sc = new Scanner(System.in);

	public static void main(String... args)
	{
		int cases = sc.nextInt();

		for (int i = 0; i < cases; i++)
			testcase(i+1);
	}

	public static void testcase(int tcase)
	{
		int n = sc.nextInt();
		HashSet<Gnu> gnus = new HashSet<Gnu>(n+1);

		for (int i = 0; i < n; i++)
		{
			gnus.add(new Gnu(sc.nextDouble(), sc.nextDouble()));
		}
		
		if (gnus.size() == 1)
		{
			System.out.printf("Data set #%d contains a single gnu.%n", tcase);
			return;
		}
		
		ArrayList<Gnu> gnulst = new ArrayList<Gnu>(gnus);
		
		int best = 0;
		
		for (Gnu g : gnus)
		{
			int res = work(gnulst, g);
			
			if (res > best)
				best = res;
		}

		System.out.printf("Data set #%d contains %d gnus, out of which a maximum of %d are aligned.%n",
				tcase, gnus.size(), best);
	}
	
	static int work(ArrayList<Gnu> gnus, Gnu zero)
	{
		for (Gnu g : gnus)
			g.setAngle(zero);
		
		Collections.sort(gnus);
		
		double alpha = Double.NaN;
		int row = 0;
		int bestrow = 0;
		
		for (Gnu g : gnus)
		{
			if (g == zero)
				continue;
			
			if (Math.abs(g.angle - alpha) <= 0.0000001)
			{
				row++;
				
			} else
			{
				
				alpha = g.angle;
				row = 2; //current (g) + zero
			}
			
			if (row > bestrow)
				bestrow = row;
		}
		
		return bestrow;
	}
}

class Gnu implements Comparable<Gnu>
{
	double x = -1;
	double y = -1;
	double angle = -1;

	public Gnu(double xx, double yy)
	{
		x = (xx == -0 ? 0 : xx);
		y = (yy == -0 ? 0 : yy);
	}
	
	public void setAngle(Gnu zero)
	{
		angle = Math.atan2(x - zero.x, y - zero.y);
		
		if (angle < 0)
			angle += Math.PI;
	}
	
	public int compareTo(Gnu g)
	{
		if (angle == g.angle)
			return 0;
		
		return (angle < g.angle ? -1 : 1);
	}

	public int hashCode()
	{
		final int prime = 31;
		int result = 1;
		long temp;
		temp = Double.doubleToLongBits(x);
		result = prime * result + (int) (temp ^ (temp >>> 32));
		temp = Double.doubleToLongBits(y);
		result = prime * result + (int) (temp ^ (temp >>> 32));
		return result;
	}

	public boolean equals(Object obj)
	{
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		Gnu other = (Gnu) obj;
		if (Double.doubleToLongBits(x) != Double.doubleToLongBits(other.x))
			return false;
		if (Double.doubleToLongBits(y) != Double.doubleToLongBits(other.y))
			return false;
		return true;
	}
	
	
}