using System;

using System.Linq;

using System.Collections.Generic;

using System.Text;

public class Program

{

    public static void Main()

    {

        // All the foreach can be replaced with Linq, too lazy lol

        Console.WriteLine("Hello World");

        int[] arr1 = {3,1,2,2,4};

        int[] arr2 = {8,5,5,5,5,1,1,1,4,4};

        sort(arr1.ToList());

        sort(arr2.ToList());

    }

    static void sort(IEnumerable<int> arr)

    {

        var frequency = new Dictionary<int, int>();

        foreach(var a in arr)

        {

            if(!frequency.ContainsKey(a))

            {

                frequency.Add(a, 0);

            }

            frequency[a] += 1;

        }

        print(frequency);

        // Here just do what is essentially a group by dict.value, CBF messing with IGrouping

        var groups = group_by_frequency(frequency);

        print_groups(groups);

        final_print(groups);

    }

    static void final_print(IDictionary<int, IEnumerable<int>> unsortedGroups)

    {

        var allKeys = unsortedGroups.Keys.ToList();

        allKeys.Sort();

        foreach(var k in allKeys)

        {

            var sortedValues = unsortedGroups[k];

            foreach(var sval in sortedValues)

            {

                var o = get_output(sval, k);

                Console.WriteLine(o);

            }

        }

    }

    static string get_output(int number, int frequency)

    {

        var s = new StringBuilder();

        for(int i = 0; i < frequency; ++i)

        {

            s.Append(number);

            s.Append(" ");

        }

        return s.ToString().TrimEnd();

    }

    static IDictionary<int, IEnumerable<int>> group_by_frequency(IDictionary<int, int> dict)

    {

        var groups = new Dictionary<int, IEnumerable<int>>();

        var allFrequencies = dict.Values.Distinct();

        foreach(var freq in allFrequencies)

        {

            var keysWithMatchingFrequency = dict.Where(x => x.Value == freq).Select(x => x.Key).ToList();

            keysWithMatchingFrequency.Sort();

            groups.Add(freq, keysWithMatchingFrequency);

        }

        return groups;

    }

    static void print(IDictionary<int, int> dict)

    {

        Console.Write("dict: ");

        foreach(var k in dict.Keys)

        {

            Console.Write(string.Format("({0}, {1}) ", k, dict[k]));

        }

        Console.WriteLine();

    }

    static void print_groups(IDictionary<int, IEnumerable<int>> dict)

    {

        Console.Write("dict: ");

        foreach(var k in dict.Keys)

        {

            Console.Write(string.Format("({0},{1}) ", k, print_list(dict[k])));

        }

        Console.WriteLine();

    }

    static string print_list(IEnumerable<int> lst)

    {

        var sb = new StringBuilder();

        foreach(var i in lst)

        {

            sb.Append(" " + i);

        }

        return sb.ToString();

    }

}