#include<iostream>
#include<string.h>
using namespace std;

int main()
{
    char n[10];

    while(cin >> n){
        int sum = 0;
        for(int i = 0; i < strlen(n); i++){
            if(n[i] == '0' || n[i] == '6' || n[i] == '9')
                sum++;
            else if(n[i] == '8')
                sum += 2;
        }
        cout << sum << endl;
    }
    return 0;
}