#include <algorithm>
#include <iostream>
#include <vector>
using namespace std;
int main(void) {
  string S;
  cin >> S;
  int score = 0;
  for(int i = 0; i < 9; i++) {
    score += (S[i] - '0');
    if('0' == S[i]) {
      score += 10;
    }
  }
  cout << score;
  return 0;
}