class Program
{
    static void Main(string[] args)
    {
        string input = Console.ReadLine()!;
        int sum = 0;

        foreach (char c in input)
        {
            string change = c.ToString();
            int score = int.Parse(change);

            if (score == 0)
            {
                sum += 10;
            }
            else
            {
                sum += score;
            }
        }

        Console.WriteLine(sum);
    }
}