#include<iostream>
#include<string>
#include<vector>
#include<algorithm>
#include<map>
#define all(x) x.begin(),x.end()
#define pb push_back
#define ll long long 
#define P pair<int,int>
#define LP pair<ll,ll>
using namespace std;
int main() {
	int sum = 0;
	string s;
	cin >> s;
	for (int i = 0; i < 9; i++) {
		if (s[i] == '0') sum += 10;
		else sum += s[i] - 48;
	}
	 cout << sum << endl;

	return 0;
}