using System;

public class Program

{

    public static void Main()

    {

        int[] randomArray = new int[50];

        Random r = new Random();

        for (int i = 0; i < randomArray.Length; i++)

        {

            randomArray[i] = r.Next(0, Math.Max(21, randomArray.Length));

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

            {

                if (randomArray[j] == randomArray[i])

                {

                    i--;

                    break;

                }

            }

        }

        Console.WriteLine("[{0}]", string.Join(", ", randomArray));

    }

}