JAVA：如何输入 ( < 0 ) 来破解密码？

Question

2 周后。我需要用一个负整数打破 while 循环，但我一直无法成功实现它。这是我在左右编辑无济于事之前的原始代码。 Print 中的值在循环之外。

public class AssignmentQuestion2 {
    public static void main(String[] args) {
        //write your code here

        ArrayList<Integer> rainfall = new ArrayList<Integer>();
        Scanner in = new Scanner(System.in);

        System.out.println("Please input rainfall(Input negative value to exit)");
        while (in.hasNextInt()) {
            if (in.hasNextInt()) {
                rainfall.add(in.nextInt()); //how to input into array

                System.out.println(calculateAverage(rainfall)); //average
                System.out.println(findSmallest(rainfall)); //smallest input
                System.out.println(findLargest(rainfall)); //largest input
            } else {
                in.close();
            }
        }
    }

Answer 1

您可以使用（恰当命名的）break 语句来中断循环：

    int r;
    while ((rainfall != null)) {
        if (in.hasNextInt()) {
            r = in.nextInt();
            if (r < 0) {
                 break;
            }

            rainfall.add(r); //how to input into array

            System.out.println(calculateAverage(rainfall)); //average
            System.out.println(findSmallest(rainfall)); //smallest input
            System.out.println(findLargest(rainfall)); //largest input
        }
    }