fn main() {
    let mut s = String::new();
    std::io::stdin().read_line(&mut s).ok();
    let s = s.trim();

    let score = s.chars().fold(0, |acc, c| {
        acc + match c {
            '0' => 10,
            c => c.to_digit(10).unwrap(),
        }
    });

    println!("{}", score);
}