结构体初始化数组

Question

您好，我正在开发一个程序，我必须初始化一副纸牌。我正在使用一个结构来表示一张卡片。但是我没有正确填写它，因为当我显示一副牌时我得到一堆零。我相信我的错误在这一行，但我不确定：

struct card temp = {"Clubs", value, false};

代码：

void initCards(){

    int count = 0;
    int location = 0;
    const int hand = 12;

    //add hearts
    int value=2;
    while( count < hand ){
        struct card temp = {"Hearts", value, false};
        cards[location] = temp;
        value++;
        count++;
    }

    count = 0;

    //add diamonts
    value = 2;
    while( count < hand ){
        struct card temp = {"Diamonds", value, false};
        cards[count] = temp;
        value++;
        count++;
    }

    //add spades
    count = 0;
    value = 2;
    while( count < hand ){
        struct card temp = {"Spades", value, false};
        cards[count] = temp;
        value++;
        count++;
    }

    //add clubs
    count = 0;
    value = 2;
    while( count < hand ){
        struct card temp = {"Clubs", value, false};
        cards[count] = temp;
        value++;
        count++;
    }

    //print the deck
    for(int i=0; i<52; i++){
        cout << cards[i].type << " " << cards[i].rank << endl;
    }
}

我不敢相信我正在使用 count 作为我的迭代器... location 是我打算使用的。而且由于我从 2 开始数，手应该是 13。有时你只需要休息一下，然后回来看看错误。这工作正常：

void initCards(){

    int count = 0;
    int location = 0;
    const int hand = 13;

    //add hearts
    int value=2;
    while( count < hand ){
        struct card temp = {"Hearts", value, false};
        cards[location] = temp;
        value++;
        location++;
        count++;
    }

    count = 0;

    //add diamonts
    value = 2;
    while( count < hand ){
        struct card temp = {"Diamonds", value, false};
        cards[location] = temp;
        value++;
        location++;
        count++;
    }

    //add spades
    count = 0;
    value = 2;
    while( count < hand ){
        struct card temp = {"Spades", value, false};
        cards[location] = temp;
        value++;
        location++;
        count++;
    }

    //add clubs
    count = 0;
    value = 2;
    while( count < hand ){
        struct card temp = {"Clubs", value, false};
        cards[location] = temp;
        value++;
        location++;
        count++;
    }


    for(int i=0; i<52; i++){
        cout << cards[i].type << " " << cards[i].rank << endl;
    }
}

Answer 1

每次添加新套装时，您都会将 count 重置为零。因此，假设cards 大到足以容纳 52 个元素，它们中的大多数都不会被填充，因为你一开始就一直在写。

如果您发布struct card 和cards 的声明，我们将能够更好地为您提供帮助。

Answer 2

这里有一些代码：

struct Card
{
  virtual const std::string& get_suite_name(void) const = 0;
  unsigned int value;
};

struct Spade_Card
: public Card
{
    const std::string& get_suite_name(void) const
    {
        static const std::string name = "Spades";
        return name;
    }
};

struct Heart_Card
: public Card
{
    const std::string& get_suite_name(void) const
    {
        static const std::string name = "Hearts";
        return name;
    }
};

struct Clubs_Card
: public Card
{
    const std::string& get_suite_name(void) const
    {
        static const std::string name = "Clubs";
        return name;
    }
};

#define CARDS_IN_SUITE 13
#define NUM_SUITES 4
#define CARDS_IN_DECK ((CARDS_IN_SUITE) * (NUM_SUITES))

int main(void)
{
    std::vector<Card *> deck;
    // Create the hearts suite & add to the deck.
    unsigned int i = 0;
    for (i = 0; i < CARDS_IN_SUITE; ++i)
    {
        Card * p_card = new Spade_Card;
        if (!p_card)
        {
            cerr << "Error allocating memory for a card." << endl;
            return EXIT_FAILURE;
        }
        p_card->value = i + 1;
        deck.push_back(p_card);
    }

    // Repeat for other suites.

    for (i = 0; i < CARDS_IN_DECK; ++i)
    {
         delete deck[i];  // Good karma to deallocate memory.
    }
    return EXIT_SUCCESS;
}

不需要为每张卡重复套件名称。一张卡片与其他 12 张卡片共享一个套件名称。一张卡片有一个套件名称。

也许这让 OO 有点过头了。 ;-)

Answer 3

卡片数组总是被最后一个卡片类型覆盖。 您不应将 count 重置为 0，而应检查 while 条件是否小于其值 + 12。

int temp = count + 12;
while(count < temp)
{
}

此外，我建议您将卡片保存在指针数组中。这将使您节省大量复制操作，因为在这种情况下，每次将卡片分配给数组索引时，您都在复制整个结构对象。