java低值输出0

Question

我是一名 Java 新手，我的代码中出现了一个非常奇怪的问题。目标是创建一个包含 20 个随机数的数组列表，显示该数组并根据数组中的数据执行一系列计算。这必须通过 6 种方法来完成。除了最后一个方法之外，一切似乎都工作正常。它的目的是获取数组中的最小数字，但由于某种原因它只输出 0。奇怪的是，对于上面的方法来说，它工作得很好，它收集了数组中的最大数字。

我尝试对其进行故障排除，看看它是否可能来自具有空值的数组，但这不太可能，因为最高的方法似乎工作正常。最低的列表靠近底部。

感谢您的帮助，非常感谢这个新手。另外，如果您有任何其他很棒的评论，我愿意接受批评!

import java.util.Random;

public class Program7 {

    public static void main(String[] args) {

        final int listSize = 20;    // List size
        double total = 0;           // Total
        int[] ranList = new int[listSize];  // Array with random numbers
        int highest = ranList[0];   // Highest variable
        int lowest = ranList[0];    // Lowest Variable

        randomNumberList(ranList);          // Calls randomNumberList method
        displayList(ranList);               // Calls displayList method
        total = totalList(total, ranList);  // Calls totalList method
        double averageList = listAverage(total, ranList);   // Calls averageList method
        highest = listHighest(ranList, highest);    // Calls listHighest method
        lowest = lowestList(ranList, lowest);   // Calls lowestList method

        // On screen output
        System.out.println("\nHere's the total: " + total);
        System.out.println("Here's the average: " + averageList);
        System.out.println("Here's the highest number in the list: " + highest);
        System.out.println("Here's the lowest number in the list: " + lowest);

    }

    /**
     * Generates a random list
     *
     * @param ranList
     */
    public static void randomNumberList(int[] ranList) {
        for (int i = 0; i < ranList.length; i++) {
            Random generator = new Random();
            int ranNum = generator.nextInt(100) + 1;
            ranList[i] = ranNum;
        }
    }

    /**
     * Displays list
     *
     * @param ranList
     */
    public static void displayList(int[] ranList) {
        System.out.println("Here is your random list: ");
        for (int i = 0; i < ranList.length; i++) {
            System.out.print(ranList[i] + " ");
        }
    }

    /**
     * Adds elements in list
     *
     * @param total
     * @param ranList
     * @return returns total of list added together
     */
    public static double totalList(double total, int[] ranList) {
        for (int i = 0; i < ranList.length; i++) {
            total += ranList[i];
        }
        return total;
    }

    /**
     * Finds average by dividing the total with the ranList.length
     *
     * @param total
     * @param ranList
     * @return result of the averaging
     */
    public static double listAverage(double total, int[] ranList) {
        double averageList = total / ranList.length;
        return averageList;
    }

    /**
     * Steps through array via loop and finds highest value
     *
     * @param ranList
     * @param highest
     * @return the highest value
     */
    public static int listHighest(int[] ranList, int highest) {
        for (int i = 0; i < ranList.length; i++) {
            if (ranList[i] > highest) {
                highest = ranList[i];
            }
        }
        return highest;
    }

    /**
     * Steps through array via loop and finds lowest value
     *
     * @param ranList
     * @param lowest
     * @return the lowest value
     */
    public static int lowestList(int[] ranList, int lowest) {
        for (int i = 0; i < ranList.length; i++) {
            if (ranList[i] < lowest) {
                lowest = ranList[i];
            }
        }
        return lowest;
    }
}

Answer 1

在将其传递到方法之前，您将其设置为 0。

int[] ranList = new int[listSize];  // Array with random numbers (not yet, right now this is an array of all 0)
int highest = ranList[0];   // Highest variable (not really, this is 0)
int lowest = ranList[0];    // Since you didn't put anything in ranList, lowest is now 0

对于您的最高函数，这工作得很好，因为您的随机数始终高于 0。

实际上，这里的根本原因是您根本不应该将任何内容传递给这些方法，因为它们没有执行任何操作。

public static int lowestList(int[] ranList) {
    int lowest = Integer.MAX_VALUE;
    for (int i = 0; i < ranList.length; i++){
        if (ranList[i] < lowest){
            lowest = ranList[i];
        }
    }
    return lowest;
}