#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

int main(){
    
    string s;
    cin >> s;
    int score = 0;
    
    for (char x : s){
        score += ( (x == '0')  ? 10 : x - '0' );
    }
    cout << score << endl;
    return 0;

    
}