public void shuffle(CardDeck deck)
{
CardDeck tempDeck = new CardDeck();
tempDeck.assign(deck);
deck.clear();
Random rnd = new Random();
int randomIndex;
while (tempDeck.Count > 0) {
randomIndex = rnd.Next(tempDeck.Count);
AbstractCard card = tempDeck.getCardAt(randomIndex);
deck.addCard(card);
tempDeck.removeCardAt(randomIndex);
}
}