Question

我一直试图在java中对数组进行冒泡一段时间，但每次只做几次然后它跟随数组列表。

public void mysort() {
    Random randomNumbers = new Random();

    int randomArray[] = new int[20];

    for (int j = 0; j <= 19; j++) {
        randomArray[j] = randomNumbers.nextInt(200 + 1);
        for (int k = 1; k < 20; k++) {
            if (randomArray[k - 1] < randomArray[k]) {
                int hjelp = randomArray[k - 1];
                randomArray[k - 1] = randomArray[k];
                randomArray[k] = hjelp;
            }
        }
    }
    for (int i = 0; i <= 19; i++) {
        System.out.println(randomArray[i]);
    }
}

如何让我的冒泡排序正常工作？

Answer 1

您需要先填充数组。您正在尝试同时填充和排序。

填充：

for (int j = 0; j <= 19; j++ ){
        randomArray[j] = randomNumbers.nextInt(200+1);
}

排序：

BubleSort（）;

Answer 2

您的代码应该是这样的：

Random randomNumbers = new Random();
int randomArray[] = new int[20];
for (int j = 0; j <= 19; j++) {
    randomArray[j] = randomNumbers.nextInt(200 + 1);
}
for(int j=0;j<20;j++) {
    for (int k = 1; k < 20; k++) {
        if (randomArray[k - 1] < randomArray[k]) {
            int hjelp = randomArray[k - 1];
            randomArray[k - 1] = randomArray[k];
            randomArray[k] = hjelp;
        }
    }
}
for (int i = 0; i <= 19; i++) {
    System.out.println(randomArray[i]);
}

请注意，您是按降序执行此操作。如果你想按升序改变

if (randomArray[k - 1] < randomArray[k])

到

if (randomArray[k - 1] > randomArray[k])

Answer 3

您应首先填充数组，然后调用排序。你正在对阵列进行“排序”20次，但它仍然不完整。

public void mysort() {
    Random randomNumbers = new Random();

    int randomArray[] = new int[20];

    for (int j = 0; j < randomArray.length; j++) {
        randomArray[j] = randomNumbers.nextInt(200) + 1;
    }

    for (int i = 0; i < randomArray.length; i++) {
        for (int k = 1; k < randomArray.length; k++) {
            if (randomArray[k - 1] < randomArray[k]) {
                int hjelp = randomArray[k - 1];
                randomArray[k - 1] = randomArray[k];
                randomArray[k] = hjelp;
            }
        }
    }

    for (int i = 0; i < randomArray.length; i++) {
        System.out.println(randomArray[i]);
    }
}

排序数组只排序一些

3 个答案: