Question

我遇到一些问题，需要打印我的最小值和最大值。也是新的因为我编程我不明白为什么我的所有值都是小数。我将发布代码和结果。

 import java.util.Random;
import java.util.Scanner;
import java.util.*;

public class RandomArray1 
extends ArrayList<Double> 
    {
        private static final long serialVersionUID = 1L;

        public RandomArray1() 
        {
            super(); 
        }

        public static RandomArray1 getInstance(int size)
            {
                Random randomNumberGenerator = new Random();
                RandomArray1 randomArray = new RandomArray1();

            for (int i = 0; i < size; i++)
                {  
                    randomArray.add(randomNumberGenerator.nextDouble()); 
                }   

                return randomArray;
            }      



        public Double getAverage() 
        {
             if (this.size() == 0) 
            {
                 return 0d;   
            }

             Double sum = 0d;

             for (Double element : this) 
                {
                    sum = sum + element;  
                }
             return sum / this.size();
        }


       public static void main(String[] args) 
       {
           Scanner scan = new Scanner(System.in);
            System.out.print("Enter how many numbers you would like to Generate: ");

            RandomArray1 randomArray = RandomArray1.getInstance(scan.nextInt());

            System.out.println(randomArray);
            System.out.println("Average" +randomArray.getAverage()); 

            double max = Double.MIN_VALUE;
            double min = Double.MAX_VALUE;

            while (true) {

                if ( !scan.hasNextDouble())

                    break;

                Double num = scan.nextDouble();

                min = Math.min(min, num);
                max = Math.max(max, num);

            System.out.println("Max is: " + max);
            System.out.println("Min is: " + min);
       }
    }
    }

以下是我的结果......

输入您想要生成的数量：5 [0.8630040934474159,0.12949667753808425,0.5751777190226718,0.18492672539115063,0.7508377917335503] 平均值：0.5006886014265746

总是小数点，它甚至不打印＆＃34; Max是：＆＃34;或者＆＃34;敏是：＆＃34;这让我觉得这部分有问题。但我不知道它是什么......任何想法。只是想法......

while (true) {

            if ( !scan.hasNextDouble())

                break;

            Double num = scan.nextDouble();

            min = Math.min(min, num);
            max = Math.max(max, num);

        System.out.println("Max is: " + max);
        System.out.println("Min is: " + min);

Answer 1

我认为你用nextDouble()填充数组，documented为你提供0到1之间的双精度浮点数。

Answer 2

一切都好，将Arraylist改为整数和其他一切。这解决了我讨论的问题。这是代码现在的样子......工作完美！

import java.util.*;

public class RandomArray1 
extends ArrayList<Integer> 
    {
        private static final long serialVersionUID = 1L;

        public RandomArray1() 
        {
            super(); 
        }

        public static RandomArray1 getInstance(int size)
            {
                Random randomNumberGenerator = new Random();
                RandomArray1 randomArray = new RandomArray1();

            for (int i = 0; i < size; i++)
                {  
                    randomArray.add((int) randomNumberGenerator.nextInt()); 
                }   

                return randomArray;
            }      



        public Double getAverage() 
        {
             if (this.size() == 0) 
            {
                 return 0d;   
            }

             Double sum = 0d;

             for (Integer element : this) 
                {
                    sum = sum + element;  
                }
             return sum / this.size();
        }


       public static void main(String[] args) 
       {
           @SuppressWarnings("resource")
        Scanner scan = new Scanner(System.in);
            System.out.print("Enter how many numbers you would like to Generate: ");

            RandomArray1 randomArray = RandomArray1.getInstance(scan.nextInt());

            System.out.println(randomArray);
            System.out.println("Average : " +randomArray.getAverage()); 

            int max = Integer.MAX_VALUE;
            int min = Integer.MIN_VALUE;

            for (int num : randomArray) 
            {
                min = Math.min(min, num);
                max = Math.max(max, num);



            }
            System.out.println("Max is: " + max);
            System.out.println("Min is: " + min);

       }


    }

非常感谢你！

Answer 3

您的程序运行良好：

Enter how many numbers you would like to Generate: 3
[0.26063976207509887, 0.48867331377683443, 0.3864751544223266]
Average0.37859607675808665
4
Max is: 4.0
Min is: 4.0
5
Max is: 5.0
Min is: 4.0
3
Max is: 5.0
Min is: 3.0
end

但由于它希望得到一个输入，但并不是这样说的，它似乎可能已经死了＃34;只需在等待下一个输入之前包含提示：

System.out.print("Please enter next number: ");
if ( !scan.hasNextDouble())
    break;

如果您想要计算现有数组的最小值/最大值而不是新用户输入，请使用for循环迭代现有数组：

    for (double num : randomArray) {
        min = Math.min(min, num);
        max = Math.max(max, num);

        System.out.println("Max is: " + max);
        System.out.println("Min is: " + min);
    }

最小值随机数组的最大值

3 个答案: