Question

我正在开发一个由一系列卡片对象组成的甲板类。我必须为这个甲板类写的方法之一是一种排序方法，它应该按照数字对卡片进行排序，按顺序排列成一组卡片：每件西装1件，每件西装2件，每件西装3件，等等。有了这个卡类，

class card {
public:
    int number;
    string suit;
    card() {number = 1;suit = "blank";}
    card(int n, string s) {number = n; suit = s;}

    void printCard() {
        cout << number << " of " << suit << "s";
    }
};

我正在尝试为使用选择排序对数组进行排序的deck类实现一个方法。

这是我的方法sort（）的代码，在deck类中声明和定义：

void sort() {
    int min, j;
    for(int i=0;i<numCards-1;i++) {
        min = i;
        for(j=i+1;j<numCards;j++) {
            if(cardArray[i].number < cardArray[min].number)
                min = j;
        }
        if(min != i)
            swapCards(cardArray[i], cardArray[min]);
    }
}

void swapCards(card &a, card &b) {
    card temp = a;
    a = b;
    b = temp;
}

然而，当我在甲板对象d上调用它时，似乎没有任何事情发生。我已经写了一些其他的方法来洗牌，或者切换牌组并交换每一半，两者都有效，但是当我调用sort（）时，没有任何反应。我一直在通过printCards（）方法检查数组，当我调用shuffle（）或cut（）时它会改变，但在调用sort（）之后保持与前一个打印输出相同。

在main（）中：

deck d;

d.printDeck();
cout << endl;
d.shuffle();
d.printDeck();
cout << endl;
d.sort();
d.printDeck();

调试后打印输出：

1 of hearts
2 of hearts
3 of hearts
4 of hearts
5 of hearts
6 of hearts
7 of hearts
8 of hearts
9 of hearts
10 of hearts
11 of hearts
12 of hearts
13 of hearts
1 of clubs
2 of clubs
3 of clubs
4 of clubs
5 of clubs
6 of clubs
7 of clubs
8 of clubs
9 of clubs
10 of clubs
11 of clubs
12 of clubs
13 of clubs
1 of spades
2 of spades
3 of spades
4 of spades
5 of spades
6 of spades
7 of spades
8 of spades
9 of spades
10 of spades
11 of spades
12 of spades
13 of spades
1 of diamonds
2 of diamonds
3 of diamonds
4 of diamonds
5 of diamonds
6 of diamonds
7 of diamonds
8 of diamonds
9 of diamonds
10 of diamonds
11 of diamonds
12 of diamonds
13 of diamonds

7 of diamonds
6 of spades
5 of diamonds
12 of clubs
2 of diamonds
5 of spades
8 of diamonds
4 of clubs
1 of hearts
8 of clubs
10 of hearts
13 of diamonds
11 of diamonds
12 of spades
2 of hearts
3 of spades
12 of diamonds
7 of spades
11 of hearts
5 of clubs
5 of hearts
1 of spades
10 of diamonds
7 of clubs
4 of diamonds
3 of diamonds
13 of spades
13 of hearts
12 of hearts
6 of clubs
1 of diamonds
11 of spades
9 of hearts
3 of hearts
9 of diamonds
9 of clubs
10 of clubs
10 of spades
9 of spades
2 of spades
6 of hearts
8 of spades
4 of hearts
1 of clubs
11 of clubs
4 of spades
3 of clubs
2 of clubs
6 of diamonds
8 of hearts
13 of clubs
7 of hearts

7 of diamonds
6 of spades
5 of diamonds
12 of clubs
2 of diamonds
5 of spades
8 of diamonds
4 of clubs
1 of hearts
8 of clubs
10 of hearts
13 of diamonds
11 of diamonds
12 of spades
2 of hearts
3 of spades
12 of diamonds
7 of spades
11 of hearts
5 of clubs
5 of hearts
1 of spades
10 of diamonds
7 of clubs
4 of diamonds
3 of diamonds
13 of spades
13 of hearts
12 of hearts
6 of clubs
1 of diamonds
11 of spades
9 of hearts
3 of hearts
9 of diamonds
9 of clubs
10 of clubs
10 of spades
9 of spades
2 of spades
6 of hearts
8 of spades
4 of hearts
1 of clubs
11 of clubs
4 of spades
3 of clubs
2 of clubs
6 of diamonds
8 of hearts
13 of clubs
7 of hearts
Press any key to continue . . .

考虑到我已经成功地为涉及数组和类的其他项目实现了选择排序，我对于为什么似乎没有任何事情发生在数组上并没有太多的想法。我在这里做的唯一新事物是用多个变量对一组对象进行排序，但我很确定我在sort（）中比较每张卡之间的正确变量。

如果有人发现了一个明显的错误，或者想知道可能导致此问题的原因，请告知我们。帮助我解决这个问题还有很长的路要走。

编辑：为deck类和调试输出中使用的其他方法添加了代码。

Answer 1

您的问题在于选择min：

for(j=i+1;j<numCards;j++) {
    if(cardArray[i].number < cardArray[min].number)
        min = j;
}

在整个循环中，min不会改变，因此if语句没有意义。您可能需要检查cardArray[j]当前最小值：

for(j=i+1;j<numCards;j++) {
    if(cardArray[j].number < cardArray[min].number)
        min = j;
}

选择排序方法似乎什么都不做

1 个答案: