#include<bits/stdc++.h>
using namespace std;
char a[21];
int ans;
int main()
{
	cin>>a;
	for(int i=1;i<=strlen(a);i++){
	if(a[i]=='2'||a[i]=='6'||a[i]=='9'||a[i]=='0')ans++;
	if(a[i]=='8')ans+=2;
	}
	cout<<ans;
	return 0;
}