class Demo {
    public static void main(String[] args) {
        System.out.println("length " + args.length);
        int sum = 0;
        for (int i = 0; i < args.length; i++) {
            int n = 0;
            try {
                n = Integer.parseInt(args[i]);
            } catch (NumberFormatException e) {
                System.out.println("invalid number: " + args[i]);
            }
            sum += n;
        }
        System.out.println("The sum is " + sum);
    }
}