#include <iostream>
#include <string>
using namespace std;
int main() {
	string S;
	cin >> S;
	int Sum = 0;
	for (int i = 0; i < S.size(); i++) {
		if ((S[i] >= 'a' && S[i] <= 'z') || (S[i] >= 'A' && S[i] <= 'Z')) {
			continue;
		}
		int num;
		string N = S.substr(i,1);
		num = stoi(N);
		Sum = Sum + num;
	}
	cout << Sum << endl;
	return 0;
}