2 I

#include <iostream>
#include <vector>
#include <string>

using namespace std;

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

    string s;
    cin >> s;

    int m = 0;
    for (int i = 0; i < s.length(); ++i) {
        if (s[i] == '9' || s[i] == '6' || s[i] == '4' || s[i] == '0') m++;
        if (s[i] == '8') m+=2;
    }

    cout << m;

    return 0;
}