#include "bits/stdc++.h"

using namespace std;

using ll = long long;
using ld = long double;

const int INF = (1 << 30) - 1;
const ll INF64 = ((ll)1 << 62) - 1;
const double PI = 3.1415926535897932384626433832795;

const int dx[] = { 0, 1, 0, -1 };
const int dy[] = { -1, 0, 1, 0 };

int main() {
	ios::sync_with_stdio(false);
	cin.tie(0);

	string s;
	cin >> s;

	int ans = [&]() -> int {
		int score = 0;
		for (auto c : s) {
			score += c == '0' ? 10 : c - '0';
		}
		return score;
	}();
	
	cout << ans << endl;
	return 0;
}