java - 我试图让用户将数字输入到 ArrayList 中。如果用户输入 0，则对数字求和并平均

Question

该程序要求用户输入填充数组列表的数字。如果用户输入 0，则程序会将之前输入的所有数字相加并求平均值。它对我不起作用，那么我怎样才能让它工作呢？

import java.util.Scanner;
import java.io.*;
import java.util.ArrayList;

public class Calculation {
    static Toolkit tools = new Toolkit();
    public static void main(String [] args) {
        double average = 0.0;
        double sum = 0;
        int i =0;
        int num = 0;
        int nElements = 0;
        Scanner console = new Scanner(System.in);

        ArrayList<Integer> value = new ArrayList<Integer>();
        System.out.println("Enter value: ");
        num = console.nextInt();
        while(num != 0) {
            value.add(new Integer(num));
        }

        for(i = 0; i < value.size(); i++) {
             sum += value.size();
        }
        average = sum / value.size();
        System.out.println("Number of values read: " + value.size());
        System.out.println("Values sum: " + sum + "Values average: " + average);
        System.exit(0);
    }
}

Answer 1

您需要阅读循环内部，这里有:

 public static void main(String [] args) {
     double average = 0.0;
     double sum = 0;
     int i =0;
     int num = 0;
     int nElements = 0;
     Scanner console = new Scanner(System.in);

     ArrayList<Integer> value = new ArrayList<Integer>();

     System.out.println("Enter value: ");
     num = console.nextInt();

     while(num != 0) {
         value.add(new Integer(num));
         num = console.nextInt();
     }

     for(i = 0; i < value.size(); i++) {
         sum += value.get(i);
     }
     average = sum / value.size();
     System.out.println("Number of values read: " + value.size());
     System.out.println("Values sum: " + sum + " Values average: " + average);
     System.exit(0);
}