package main

import (
	"fmt"
	"strconv"
)

func main() {
	var s string
	var a, t int
	fmt.Scan(&s)
	for i := 0; i < len(s); i++ {
		a, _ = strconv.Atoi(string(s[i]))
		if a == 0 {
			t += 10
		} else {
			t += a
		}
	}
	fmt.Println(t)
}