using System;

using System.Collections.Generic;

using System.Linq;

public class Program

{

    public static void Main()

    {

        var lotto = Enumerable.Range(0, 50).Shuffle(new Random()).Take(7);

        Console.WriteLine("the new lotto winning numbers are: {0}", string.Join(",", lotto));

    }

​

}

​

public static class Extensions

{

    public static IEnumerable<T> Shuffle<T>(this IEnumerable<T> source, Random rng)

    {

        T[] elements = source.ToArray();

        for (int i = elements.Length - 1; i >= 0; i--)

        {

            int swapIndex = rng.Next(i + 1);

            yield return elements[swapIndex];

            elements[swapIndex] = elements[i];

        }

    }

}