using System.Linq;
using System.Collections.Generic;
using System;

public class Hello
{
    static void Main()
    {

        string[] line = Console.ReadLine().Trim().Split(' ');
        var n = int.Parse(line[0]);
        var k = int.Parse(line[1]);
        line = Console.ReadLine().Trim().Split(' ');
        var a = Array.ConvertAll(line, int.Parse);
        getAns(n, k, a);
    }
    static void getAns(int n, int k, int[] a)
    {
        var d = new Dictionary<int, int>();
        foreach (var x in a)
            if (d.ContainsKey(x)) d[x]++;
            else d[x] = 1;
        var ans = 0;
        var c = 0;
        foreach (var x in d.OrderByDescending(x => x.Value))
        {
            if (c + x.Value < k) { ans++; c += x.Value; }
            else { Console.WriteLine(ans + 1); return; }
        }
        Console.WriteLine(ans);
    }
}