#include <stdio.h>
#include <math.h>

int main (void)
{
  int K, k, N, n;
  double a[202];
  float f, r;
  double pi = atan2(0,-1);
  int p[202];
  int s;
  char possible;

  FILE *in = fopen ("probleme.in", "r");

  fscanf (in, "%d\n", &K);

  for (k = 1; k <= K; k ++)
    {
      fscanf (in, "%d\n", &N);
      for (n = 0; n < N; n ++)
	{ fscanf (in, "%f %f\n", &f, &r); a[n] = (double) f;}
      possible = 0;
      s = N;
      while (s >= 1 && !possible)
	{
	  int i, j;
	  for (i = 0; i < N && !possible; i ++) 
	    {
	      possible = 1;
	      for (j = 0; j < s; j ++) p[j] = 0;
	      for (j = 0; j < N; j ++)
		{
		  double ca = a[j] - a[i];
		  while (ca < 0.0) ca = ca + 2.0*pi;
		  while (ca > 2.0*pi) ca = ca - 2.0*pi;
		  ca = ca*((double) s)/(2.0*pi);
		  p[(int) ca] ++;
		}
	      for (j = 0; j < s; j ++) if (p[j] != N/s) possible = 0;
	    }
	  if (!possible) s --;
	}
      printf ("Data Set %d: %d slices\n", k, s);
      if (k < K) printf ("\n");	      
    }

  fclose (in); 
  return 0;
}