System.out.println("items: ");

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

            if (sc.hasNextInt())
            a[i] = sc.nextInt();

        else {
            System.out.println("input-output error");
            sc.close();
            return;
            }
        }
        sc.close();

        switch (numurs) {

        case 1: firstMethod(a);
        break;
        case 2: secondMethod(a);
        break;

        default:
            System.out.println("input-output error");
        return;
        }