/* ========================================================================
   $File: $
   $Date: $
   $Revision: $
   $Creator: Creative GP $
   $Notice: (C) Copyright 2017 by Creative GP, Inc. All Rights Reserved. $
   ======================================================================== */

#define CPP

#include <iostream>
#include <string>
#include <cstdlib>

using namespace std;

int main()
{
    string s;
    cin >> s;
    int ans = 0;
    for (int i = 0; i < 9; i++) {
        ans += (s[i]=='0')?10:(s[i]-'0');
    }
    cout << ans << endl;
}