分段故障:11个指针和结构

Question

我在头文件中创建了两个结构，一个用于卡片，另一个用于处理，如下所示：

struct Card 
{                                 
    char *face; // define pointer face 
    char *suit; // define pointer suit
};


struct Hand
{
    struct Card *cards[15]; // define an array to hold a card
    char hand[13];  // defines the type of hand 
};

在我的printHand函数中，我尝试向每只手添加一张卡片，然后将这些手添加到一个代表所有玩家的数组中。我运行了一个调试器，在这里发生了分段错误：

// Here we will add the cards to the array holding the player's hands
totalHands[indexHand].cards[indexCard]->face = shuffledDeck[indexCard].face;
totalHands[indexHand].cards[indexCard]->suit = shuffledDeck[indexCard].suit;

调试器打印EXC_BAD_ACCESS。这是我的功能：

void printHand(struct Card* shuffledDeck, char* argv[])
{
    // total number of cards
    const int DeckMaxSize = 53;

    // get the command line input
    int numOfHands = atoi(argv[1]);
    int numOfCards = atoi(argv[2]);

    // counters for our loops
    int indexHand;
    int indexCard;

    struct Hand totalHands[10]; // an array holding all the hands

    // allocate memory for our struct
    struct Hand* tempHand = (struct Hand*)malloc(numOfCards * sizeof(struct Hand));

    // Adjusted the command line arguments if the number cards/hand and
    // players can not be resolved from a 52 sized deck
    int validateInput = DeckMaxSize / numOfHands;

    if (validateInput < numOfCards) {
        numOfCards = validateInput;
        printf("\n%s", "Input was adjusted to the size of the deck ( 52 )");
    }

    // Creates a new Hand and adds it to the totalHands[]
    for (indexHand = 1; indexHand <= numOfHands; indexHand++) {
        totalHands[indexHand] = *tempHand;
        printf("\n\n%s %d\n", "Player : ", indexHand);

        // add the cards to the hand and print each player's hand
        for (indexCard = 1; indexCard <= numOfCards; indexCard++) {
            // Here we will add the cards to the array holding the player's hands
            totalHands[indexHand].cards[indexCard]->face = shuffledDeck[indexCard].face;
            totalHands[indexHand].cards[indexCard]->suit = shuffledDeck[indexCard].suit;

            // Print all of our player's hand
            printf("\n%d %s ", indexCard, totalHands[indexHand].cards[indexCard]->face);
            printf("%s", totalHands[indexHand].cards[indexCard]->suit);
        }

        // print a new line for formatting
        printf("\n");
    }
}

Answer 1

for(indexHand = 1; indexHand <= numOfHands; indexHand++){
...
for(indexCard = 1; indexCard <= numOfCards; indexCard++){       

这些循环从1到n(最大索引包括)。但是索引应该从0到n-1。因此，这些循环访问索引超出界限。

把你的循环修改成-

for(indexHand = 0; indexHand < numOfHands; indexHand++){
...
for(indexCard = 0; indexCard < numOfCards; indexCard++){       

编辑-

 totalHands[indexHand].cards[indexCard]->face = shuffledDeck[indexCard].face;
totalHands[indexHand].cards[indexCard]->suit = shuffledDeck[indexCard].suit;

在这两种语句之前，您不会为指针cards数组分配内存，但是您会取消引用它(未初始化的指针)。

分配此数组的内存指针，然后访问数组成员。