using System;

using System.Collections.Generic;

public class Program

{

    public static bool CheckUniqueOccurrences(int[] arr) 

    {

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

        foreach (int n in arr)

        {

            if (!freq.ContainsKey(n)) freq[n] = 0;

            freq[n]++;

        }

        var unique = new HashSet<int>(freq.Values);

        return freq.Count == unique.Count;

    }

    public static void Main()

    {

        Console.WriteLine("UniLecs");

        Console.WriteLine(CheckUniqueOccurrences(new int[] { 1, 2, 3 }).ToString()); // False

        Console.WriteLine(CheckUniqueOccurrences(new int[] { 1, 2, 2, 3, 3, 3 }).ToString()); // True

    }

}