import java.util.Scanner;

class Q656 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String s = sc.nextLine();
        char[] c = s.toCharArray();
        int result = 0;
        for(int i = 0; i<9; i++) {
            if(Character.getNumericValue(c[i]) == 0) {
                result += 10;
            } else {
                result += Character.getNumericValue(c[i]);
            }
        }
        System.out.println(result);
    }
}