import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class SumNum{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        String numstr = sc.next();
        String[] ns = numstr.split("");

        int sum_ = 0;
        for(int i=0; i<ns.length; i++){
            Pattern p = Pattern.compile("^[0-9]+$");
            Matcher m = p.matcher(ns[i]);
            if(m.find()){
                sum_ += Integer.parseInt(ns[i]);
            }
        }
        System.out.println(sum_);
    }
}