Fisher-Yates Shuffle

FisherYatesShuffle.cs

private static IEnumerable<Card> Shuffle(IList<Card> cards)
{
    var rnd = new Random();
    for (var n = cards.Count - 1; n > 0; --n)
    {
        var newPosition = rnd.Next(n + 1);
        var temp = cards[n];
        cards[n] = cards[newPosition];
        cards[newPosition] = temp;
    }
    return cards;
}