using System;

​

public class Program

{

    public static void Main()

    {

        int[] stream = {1, 2, 234, 5, 3, 5, 7, 8, 35, 6, 67, 8, 4, 3, 33, 3, 3, 4, 6, 7, 8, 4, 3, 3, 2, 5, 78, 45, 64, 46, 456, 46, 456, 456, 456, 456, 4564, 6545, 645, 6456, 45, 645, 645, 645, 645, 645, 64, 432, 423, 423, 64};

        int k = 5;

        int[] sample = new int[k];

        int i = 0;

        for (i = 0; i < sample.Length; i++)

        {

            sample[i] = stream[i];

        }

​

        for (; i < stream.Length; i++)

        {

            Random rnd = new Random();

            int j = rnd.Next(int.MaxValue);

            j = j % (i + 1);

            if (j < k)

            {

                sample[j] = stream[i];

            }

        }

​

        Console.WriteLine("Random Numbers\n\n" + string.Join(" ", sample));

        int n = 50;

        bool[] prime = new bool[n];

        for (int d = 0; d < n; d++)

        {

            prime[d] = true;

        }

​

        for (int g = 2; g <= Math.Sqrt(n); g++)

        {

            if (prime[g] == true)

            {

                for (int b=0, j = (int)Math.Pow(g, 2) + g * b ; j < n; b++, j = (int)Math.Pow(g, 2) + g * b)

                {

                    prime[j] = false;

                }

            }

        }

​

        Console.WriteLine("\n\nPrime number 1-50 \n");

        for (int l = 0; l < n; l++)

        {

            if (prime[l]==true)

                Console.Write(l + "\t");

        }

    }

}