#include <stdio.h>
#include <string.h>

#define MACHINES 501

int main (void){

  int k, K;
  int p, m, j;
  int machine;
  int unsuccessful;
  int busyMachines[MACHINES];

  FILE *in = fopen ("seat.in", "r");
  fscanf (in, "%d\n", &K);
  for (k = 1; k <= K; k ++){

    unsuccessful=0;
    memset(busyMachines,0,sizeof(busyMachines));

    fscanf (in, "%d %d\n", &p, &m);
    for (j = 0; j < p; j ++){
      fscanf (in, "%d\n", &machine);
      if(busyMachines[machine])unsuccessful++;
      busyMachines[machine]++;
    }
      printf ("Data Set %d:\n", k);
      printf ("%d\n", unsuccessful);
  }

  fclose (in);
  return 0;
}