#include <iostream>
#include <string>
#define N 10000
using namespace std;
int main() {
    int i, s = 0;
    char a;
    for (i=0; i<N; i++) {
        a = getchar();
        if (a >= 48 && a <= 57) {
            s += a - 48;
        } else if ((a >= 65 && a <= 90) || (a >=  97 && a <= 122)) {
            continue;
        } else {
            break;
        }
    }
    cout << s << endl;
    return 0;
}