c# 直接检查扑克牌

Question

我正在尝试用 C# 编写一个扑克牌评估方法。除了顺子之外，我已经成功地为使用 linq 的每一手扑克牌做到了这一点。 对于那些不玩顺子的人来说，顺子由 5 张牌组成，每张牌增加 1 点。 A 可以高也可以低。

我创建了一个名为 card 的对象，它具有花色、等级和值(value)(J = 11，Q = 12 等)。我的方法将传递一个包含 7 张牌(底牌和棋盘)的对象列表。

另一件要记住的事情是，只有当玩家有 5 或 10 时才能形成顺子。

请参阅下面我针对其他扑克手牌的方法，如果您对直接方法有任何想法，请告诉我。伪代码也可以。

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public bool CheckPair(List<Card> cards)
{
    //see if exactly 2 cards card the same rank.
    return cards.GroupBy(card => card.Rank).Count(group => group.Count() == 2) == 1;
}

public bool CheckTwoPair(List<Card> cards)
{
    //see if there are 2 lots of exactly 2 cards card the same rank.
    return cards.GroupBy(card => card.Rank).Count(group => group.Count() >= 2) == 2;
}

public bool CheckTrips(List<Card> cards)
{
    //see if exactly 3 cards card the same rank.
    return cards.GroupBy(card => card.Rank).Any(group => group.Count() == 3);
}
public bool CheckStraight(List<Card> cards)
{
    // order by decending to see order
    var cardsInOrder = cards.OrderByDescending(a => a.Value).ToList();
    // check for ace as can be high and low
    if (cardsInOrder.First().Rank == "A")
    {
        // check if straight with ace has has 2 values
        bool highStraight = cards.Where(a => a.Rank == "K" || a.Rank == "Q" || a.Rank == "J" || a.Rank == "10").Count() == 4;
        bool lowStraight = cards.Where(a => a.Rank == "2" || a.Rank == "3" || a.Rank == "4" || a.Rank == "5").Count() == 4;
        // return true if straight with ace
        if (lowStraight == true || highStraight == true)
        {
            return true;
        }
    }
    else
    {
        // check for straight here
        return true;
    }
    // no straight if reached here.
    return false;

}

public bool CheckFlush(List<Card> cards)
{
    //see if 5 or more cards card the same rank.
    return cards.GroupBy(card => card.Suit).Count(group => group.Count() >= 5) == 1;
}

public bool CheckFullHouse(List<Card> cards)
{
    // check if trips and pair is true
    return CheckPair(cards) && CheckTrips(cards);
}
public bool CheckQuads(List<Card> cards)
{
    //see if exactly 4 cards card the same rank.
    return cards.GroupBy(card => card.Rank).Any(group => group.Count() == 4);
}

// need to check same 5 cards
public bool CheckStraightFlush(List<Card> cards)
{
    // check if flush and straight are true.
    return CheckFlush(cards) && CheckStraight(cards);
}

Answer 1

这可能不是性能最好的检查，但我会说它的可读性很强，这通常是一个很好的属性。

只需抓取 5 张牌，每次迭代时跳过您已经看过的牌，并检查每个序列的顺子。如果有序序列不包含 double 并且第一张和最后一张牌的差值为 5，则它是顺子。

public bool CheckStraight(List<Card> cards)
{
     //maybe check 5 and 10 here first for performance

     var ordered = cards.OrderByDescending(a => a.Value).ToList();
     for(i = 0; i < ordered.Count - 5; i++) {
          var skipped = ordered.Skip(i);
          var possibleStraight = skipped.Take(5);
          if(IsStraight(possibleStraight)) {
               return true;
          }
     }
     return false;
}

public bool IsStraight(List<Card> fiveOrderedCards) {
     var doubles = cards.GroupBy(card => card.Rank).Count(group => group.Count() > 1);
     var inARow = cards[4] - cards[0] = 5; //Ace is 0

     return !doubles && inARow;
}