public class ArrayTest {

    public static void main(String[] args) {
        int[] arr = new int[5];
        for (int i = 0; i < 5; i++) {
            arr[i] = i;
        }
        int sum = 0;
        for (int i = 0; i < 5; i++) {
            sum += arr[i];
        }
        System.err.println("Sum of numbers from 0 to 4:" + sum);
    }
}