#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (n); ++i)
using ll = long long;
using P = pair<int, int>;

int main(void)
{
  string s;
  cin >> s;

  int score = 0;
  rep(i, s.size())
  {
    int now = s[i] - '0';
    if (now == 0)
      score += 10;
    else
      score += now;
  }

  cout << score << endl;
  return 0;
}