DeckManager

Card[] cards;
public int Count { get; private set; }

public void Shuffle() {
    List<Card> deck = new List<Card>();
    int i, x;
    for(i = 0; i < Count; i++)
        deck.Add(cards[i]);

    for(i = 0; i < Count; i++) {
        x = rand.Next(deck.Count);
        cards[i] = deck[x];
        deck.RemoveAt(x);
    }
}

public void AddOnTop(Card card) {
    cards[Count++] = card;
}

public void AddOnBottom(Card card) {
    for(int i = Count; i > 0; i--)
        cards[i] = cards[i - 1];
    Count++;
    cards[0] = card;
}

public void AddRandom(Card card) {
    int x = rand.Next(Count);
    for(int i = Count; i > x; i--)
        cards[i] = cards[i - 1];
    Count++;
    cards[x] = card;
}

public Card RemoveFromTop() {
    return cards[--Count];
}

public Card RemoveFromBotton() {
    Card r = cards[0];
    for(int i = 1; i < Count; i++)
        cards[i - 1] = cards[i];
    Count--;
    return r;
}

public Card RemoveRandom() {
    int x = rand.Next(Count);
    Card r = cards[x];
    for(int i = x + 1; i < Count; i++)
        cards[i - 1] = cards[i];
    Count--;
    return r;
}