---

5


import java.util.Arrays;

class Main {
    public static void main(String[] args) {

        int[] a = {1, 2, 3, 4, 5, 6};

        for (int i = 0; i < a.length - 1; i = i + 2) {

            int t = a[i];

            a[i] = a[i + 1];

            a[i + 1] = t;
        }

        System.out.println(Arrays.toString(a));
    }
}






4



7import java.util.Arrays;

class Main {
    public static void main(String[] args) {

        int[] a = {1, 2, 3, 4, 5};

        int[] b = new int[a.length];

        for (int i = 0; i < a.length; i++) {
            b[i] = a[a.length - 1 - i];
        }

        System.out.println(Arrays.toString(b));
    }
}