#include <stdio.h>
#include <stdlib.h>

int cmp_int_rev (const void *ap, const void *bp) {
  int a = *(int *)ap;
  int b = *(int *)bp;
  
  if (a < b) {
    return 1;
  }
  
  if (a > b) {
    return -1;
  }
  
  return 0;
}

int main () {
  int n = 0;
  int k = 0;
  int a = 0;
  
  int res = 0;
  
  int ans = 0;
  int cnt[100000] = {};
  int sum = 0;
  
  res = scanf("%d", &n);
  res = scanf("%d", &k);
  for (int i = 0; i < n; i++) {
    res = scanf("%d", &a);
    cnt[a-1]++;
  }
  
  qsort(cnt, n, sizeof(int), cmp_int_rev);
  
  while (sum < k) {
    sum += cnt[ans];
    ans++;
  }
  
  printf("%d\n", ans);
  return 0;
}