private static void printArr(int[] arrHead, int[] arrTail) {
        System.out.print(++counter + ": ");
        if (arrHead != null && arrHead.length != 0) {
            for (int item : arrHead) {
                System.out.print(item);
            }
        }
        if (arrTail != null && arrTail.length != 0) {
            for (int item : arrTail) {
                System.out.print(item);
            }
        }
       
        System.out.println();
    }