Java 数组 - 将字符串放在哪里？为什么它不起作用？

Question

我的程序应该是这样的：

How many random numbers between 0 - 999 do you want? 12 (user input)

Here are the random numbers: 145 538 56 241 954 194 681 42 876 323 2 87

These 7 numbers are even: 538 56 954 194 42 876 2

These 5 numbers are odd: 145 241 681 323 87

我似乎无法将 Strings（"These 7 numbers are even" 和 "These 5 numbers are odd" 放在代码的正确位置。我如何打印确切的数字（7 和 5) 显示在 String 中的偶数和奇数？代码似乎对我来说无论哪种方式都不起作用。你看到问题了吗？我希望你能帮我解决这个问题，我已经连续做了 12 个小时了。

这是我的代码：

import java.util.Scanner;

public class SlumpadeTal {

    public static void main(String[] args) {

        int evenCounter = 0;
        int oddCounter = 0; 

        Scanner input = new Scanner(System.in);
        System.out.println("How many random numbers between 0 - 999 do you want?");
        int antal = input.nextInt();

        System.out.println("Here are the random numbers:");

        int[] arrayen = new int[antal];
        for (int i = 0; i < arrayen.length; i++) {
            arrayen[i] = (int) (Math.random() * 999 + 1);

            System.out.print(arrayen[i] + " ");
            if ((arrayen[i] % 2) == 0) {
                evenCounter++;
            }
            else {
                oddCounter++;
            }
        }
        int[] evenArray = new int [evenCounter];
        int[] oddArray = new int[oddCounter];
        evenCounter = 0;
        oddCounter = 0;
        for (int i = 0; i < arrayen.length; i++){
            if ((arrayen[i] % 2) == 0) {
                evenArray[evenCounter] = arrayen[i];
                evenCounter++;
            }
            else {
                oddArray[oddCounter] = arrayen[i];
                oddCounter++;
            }       
        }
    }
}

注意我不能使用任何 class，例如 ArrayList、Vector 等等。

Answer 1

当 evenArray 和 oddArray 在最后一个 for 循环完成后有值时。您只需使用 2 个另一个循环来打印这 2 个数组。

7 是 evenCounter + 1

5 是 oddCounter + 1

例如： String s = "These " + (evenCounter + 1) + "numbers are even: " ....打印你的数组。

Answer 2

只为你的输出：

System.out.print("These "+evenCounter+" numbers are even: ");
for (int i = 0; i < evenCounter; i++){
    System.out.print(evenArray[i]+" ");
}
System.out.println();
System.out.print("These "+oddCounter+" numbers are odd: ");
for (int i = 0; i < oddCounter; i++){
    System.out.print(oddArray[i]+" ");
}
System.out.println();

可以，还有其他解决方案。例如：

String evStr=new String();
String odStr=new String();

int curNum=0;
for (int i = 0; i < antal; i++) {
    curNum = (int) (Math.random() * 999 + 1);

    System.out.print(curNum + " ");
    if ((curNum % 2) == 0) {
        evStr+=" "+curNum;
        evenCounter++;
    }
    else {
        odStr+=" "+curNum;
        oddCounter++;
    }
}
System.out.println();
System.out.println("These "+evenCounter+" numbers are even: "+evStr);
System.out.println("These "+oddCounter+" numbers are odd: "+odStr);

因此带有 even/odd 数组的代码的整个第二部分都消失了。而且再也没有数组了。

Java 数组 - 将字符串放在哪里？为什么它不起作用？

Java Arrays - Where too put Strings? Why doesn't it work?

java

arrays

random

numbers