java - 如何在 Java 中打印出数组的偶数索引？

Question

我应该编写一个程序，使用 for 循环打印出数组的偶数索引。例如，如果我创建一个包含 10 个数字的数组，它将具有 0-9 的索引，因此在这种情况下，我将打印出索引 2、4、6 和 8 处的数字。这是我到目前为止所写的，但它不起作用。请注意，我并不是要打印出数组的偶数。我只想要偶数索引。

示例我输入以下数组:3,7,5,5,5,7,7,9,9,3

程序输出:

5 // (the number at index 2)
5 // (the number at index 4)
7 // (the number at index 6)
9 // (the number at index 8)

我的代码:

public class Arrayevenindex 
{
    public static void main(String[] args)
    {
        int number; // variable that will represent how many elements the user wants the array to have

        Scanner key = new Scanner(System.in);

        System.out.println(" How many elements would you like your array to have");
        number = key.nextInt();
        int [] array = new int [number];

        // let the user enter the values of the array.  
        for (int index = 0; index < number; index ++) 
        {
            System.out.print(" Value" + (index+1) + " :");
            array[index] = key.nextInt();
        }
        // Print out the even indexes 
        System.out.println("/nI am now going to print out the even indexes");
        for (int index = 0; index < array.length; index ++) 
        {
            if (array[number+1]%2==0)
                System.out.print(array[number]);
        }
    }
}

Answer 1

你可以只改变你的 for 循环并摆脱内部 IF...

for( int index = 0; index < array.length; index += 2) {
    System.out.println(array[index]);
}