#include<bits/stdc++.h>
using namespace std;
int main(){
    string x;
    int sum=0;
    cin>>x;
    for(int i=1;i<=x.size();i++){
        if(x[i]=='2'||x[i]=='6'||x[i]=='9'||x[i]=='0') sum++;
        else if(x[i]=='8') sum+=2;
    }
    cout<<sum;
    return 0;
}