import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Arrays;

public class Main {
	public static void main(String[] args) throws Exception {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String[] sa = br.readLine().split(" ");
		int n = Integer.parseInt(sa[0]);
		int k = Integer.parseInt(sa[1]);
		sa = br.readLine().split(" ");
		int[] c = new int[n + 1];
		for (int i = 0; i < n; i++) {
			int a = Integer.parseInt(sa[i]);
			c[a]++;
		}
		br.close();

		Arrays.sort(c);
		int ans = 0;
		for (int i = n; i >= 0; i--) {
			ans++;
			k -= c[i];
			if (k <= 0) {
				break;
			}
		}
		System.out.println(ans);
	}
}