Question

我正在尝试将生成的数字放入特定范围，但它会不断给我输出：

200 Generated numbers, 10 per line: 
99 Numbers from 0-20: 1
Numbers from 20-40: 0
Numbers from 40-60: 0
Numbers from 60-80: 0
Numbers from 80-100: 0
18 Numbers from 0-20: 2
Numbers from 20-40: 0
Numbers from 40-60: 0
Numbers from 60-80: 0
Numbers from 80-100: 0
56 Numbers from 0-20: 3

这是我目前的代码：

import java.util.Random;

public class RandomStats2 {

    public static void main(String[] args) {
        Random random = new Random ();
        int[] num = new int [5];
        System.out.println("200 Generated numbers, 10 per line: ");
        int numbersOnThisLine = 0;

        for(int i = 0; i < 200; i++){
            int nextNumber = random.nextInt(101);
            System.out.print(nextNumber + " ");
            numbersOnThisLine++;    

            if (numbersOnThisLine == 10){
                System.out.print("\n");
                numbersOnThisLine = 0;
            }

            if(i <=21) num[0]++;
            else if(i <=41) num[1]++;
            else if(i <=61) num[2]++;
            else if(i <=81) num[3]++;
            else if(i <=100) num[4]++;
            System.out.println("Numbers from 0-20: " + num[0]);
            System.out.println("Numbers from 20-40: " + num[1]);
            System.out.println("Numbers from 40-60: " + num[2]);
            System.out.println("Numbers from 60-80: " + num[3]);
            System.out.println("Numbers from 80-100: " + num[4]);               
        }   
    }
}

我该如何解决这个问题？另外，我如何在else if语句中设置41-60的范围？

Answer 1

你想检查你nextNumber所以我想你想要这个：

if(nextNumber <21){ num[0]++;}
else if(nextNumber <41){ num[1]++;}
else if(nextNumber <61){ num[2]++;}
else if(nextNumber <81){ num[3]++;}
else if(nextNumber <101){ num[4]++;}

此外，无论何时使用if-else，都要使用这些{}。

其次，在循环结束后打印。

Answer 2

将调用移至System.out.println()循环之外的for将解决重复输出的问题。此外，您当前的if和else if语句未检查正确的值。试试这个：

if (nextNumber <= 20) num[0]++;
else if (nextNumber <= 40) num[1]++;
else if (nextNumber <= 60) num[2]++;
else if (nextNumber <= 80) num[3]++;
else if (nextNumber <= 100) num[4]++;

Answer 3

你真的应该在for循环中做所有这些吗？我不确定你想要完成什么，但一个疯狂的建议就是在循环之外将它打印出来。

现在您正在打印您为每个随机整数找到的内容。

Answer 4

查看代码，看起来您希望每10次迭代打印出范围。如果是这样，请在if语句中移动print语句，如下所示。

import java.util.Random;

public class RandomStats2 {

    public static void main(String[] args) {
        Random random = new Random ();
        int[] num = new int [5];
        System.out.println("200 Generated numbers, 10 per line: ");
        int numbersOnThisLine = 0;

        for(int i = 0; i < 200; i++){
            int nextNumber = random.nextInt(101);
            System.out.print(nextNumber + " ");
            numbersOnThisLine++;    

            if (numbersOnThisLine == 10){
                System.out.print("\n");
                numbersOnThisLine = 0;
                System.out.println("Numbers from 0-20: " + num[0]); 
                System.out.println("Numbers from 20-40: " + num[1]);
                System.out.println("Numbers from 40-60: " + num[2]);
                System.out.println("Numbers from 60-80: " + num[3]);
                System.out.println("Numbers from 80-100: " + num[4]);
            }

            if(i <=21) num[0]++;
            else if(i <=41) num[1]++;
            else if(i <=61) num[2]++;
            else if(i <=81) num[3]++;
            else if(i <=100) num[4]++;            
        }   
    }
}

Answer 5

您的统计信息需要像for循环一样：

import java.util.Random;

public class RandomStats2 {

public static void main(String[] args) {
    Random random = new Random ();
    int[] num = new int [5];
    System.out.println("200 Generated numbers, 10 per line: ");
    int numbersOnThisLine = 0;

    for(int i = 0; i < 200; i++){
        int nextNumber = random.nextInt(101);
        System.out.print(nextNumber + " ");
        numbersOnThisLine++;    

        if (numbersOnThisLine == 10){
            System.out.print("\n");
            numbersOnThisLine = 0;
        }

        if(i <=21) num[0]++;
        else if(i <=41) num[1]++;
        else if(i <=61) num[2]++;
        else if(i <=81) num[3]++;
        else if(i <=100) num[4]++;              
    }   
    System.out.println("Numbers from 0-20: " + num[0]);
    System.out.println("Numbers from 20-40: " + num[1]);
    System.out.println("Numbers from 40-60: " + num[2]);
    System.out.println("Numbers from 60-80: " + num[3]);
    System.out.println("Numbers from 80-100: " + num[4]); 
}

}

同样对于if语句，我认为你打算使用nextNumber而不是i，因为i是你的循环计数器

将数字放在特定范围内会产生奇怪的输出

5 个答案: