递减通过数组创建的 Carousel。我不明白哪里出了问题

Question

我不得不制作一个递减轮播 [1]：https://i.stack.imgur.com/T7E4d.png。虽然它有点管用，但我需要它 return 正确的结果，这样我才能通过测试。代码：

int position = 0;
int capacity = 3;

    public int next() {
        if (allNegative(arr)) return -1;
        
        if (position >= capacity) position = 0;
        
        if (arr[position] <= 0) {
            if (position == arr.length - 1) {
                position = 0;
                if (arr[position] == 0) {
                    return arr[++position]--;
                }
                else {return arr[position++]--;}
            }
            else {
                return arr[++position]--;
            }

        }
        return arr[position++]--;

    }

所以它将元素放入数组中，next() 方法应该 return 当前值并递减它，之后它移动到下一个元素。它应该跳过零元素。当它没有什么可减少时，它 returns -1。我一直卡在这里，我不明白什么不起作用。

一个程序的完整代码：

public class DecrementingCarousel {
    static int capacity;
    int counter = 0;
   //static List <Integer> elements = new ArrayList<>();
    static int [] arr ;


    public DecrementingCarousel(int capacity) {
        DecrementingCarousel.capacity = capacity;
        arr = new int[capacity];

    }



    public boolean addElement(int element){
        if (counter < capacity && element > 0) {
            arr[counter] = element;
            counter++;
            return true;
        }
        return false;



    }

    public CarouselRun run(){
        return new CarouselRun();
    }
}
public class CarouselRun {
    int position = 0;
    int number = 0;
    /*
            if (arr[position] > 0) return arr[position++]--;
            if (arr[position] <= 0) {
                arr = removeTheElement(arr,position);
                capacity--;
                if (position >= capacity) position = 0;
            }

            return arr[position++]--;

     */

    public int next() {
        if (allNegative(arr)) return -1;

        if (position >= capacity) position = 0;

        if (arr[position] <= 0) {
            if (position == arr.length - 1) {
                position = 0;
                if (arr[position] == 0) {
                    return arr[++position]--;
                }
                else {return arr[position++]--;}
            }
            else {
                return arr[++position]--;
            }

        }
        return arr[position++]--;

    }

        public static int[] removeTheElement(int[] arr, int index)
        {

            // If the array is empty
            // or the index is not in array range
            // return the original array
            if (arr == null || index < 0
                    || index >= arr.length) {

                return arr;
            }

            // Create another array of size one less
            int[] anotherArray = new int[arr.length - 1];

            // Copy the elements except the index
            // from original array to the other array
            for (int i = 0, k = 0; i < arr.length; i++) {

                // if the index is
                // the removal element index
                if (i == index) {
                    continue;
                }

                // if the index is not
                // the removal element index
                anotherArray[k++] = arr[i];
            }

            // return the resultant array
            return anotherArray;
        }

    public static boolean allNegative (int arr[]) {
        for (int i = 0; i < arr.length; i++) {
            if (arr[i] > 0) return false;
        }
        return true;
    }



    public boolean isFinished() {
        for (int var: arr) {
            if (var > 0) return false;
        }
        return true;

    }

}

主要方法和输出的外观：

public class Main {
    public static void main (String args[]) {
        DecrementingCarousel carousel = new DecrementingCarousel(7);

        carousel.addElement(2);
        carousel.addElement(3);
        carousel.addElement(1);

        CarouselRun run = carousel.run();

        System.out.println(run.isFinished()); //false

        System.out.println(run.next()); //2
        System.out.println(run.next()); //3
        System.out.println(run.next()); //1

        System.out.println(run.next()); //1
        System.out.println(run.next()); //2

        System.out.println(run.next()); //1

        System.out.println(run.isFinished()); //true
        System.out.println(run.next()); //-1


    }
}

Answer 1

您需要遍历数组，直到找到一个值大于 0 的索引。您还可以使用该循环来检查是否存在 any 个值大于 0:

public int next() {
    int count = 0;
    while (count < arr.length && arr[position %= arr.length] <= 0) {
        position++;
        count++;
    }
    if (count == arr.length) return -1;
    return arr[position++]--;
}

递减通过数组创建的 Carousel。我不明白哪里出了问题

Decrement Carousel created through array. I don't understand what went wrong

java

arrays

arraylist