#include <bits/stdc++.h>
using namespace std;
using ll = long long;
#define rep(i, s, e) for (int i = (int)s; i < (int)e; ++i)
#define all(a) (a).begin(), (a).end()

int main() {
    cin.tie(nullptr);
    
    string S;
    cin >> S;
    
    int ans = 0;
    rep(i, 0, 9) {
        if (S[i] == '0') ans += 10;
        else ans += S[i] - '0';
    }
    
    cout << ans << '\n';
}