code：

#include<bits/stdc++.h>
using namespace std;
typedef pair<int,int> pii;
typedef long long ll;
inline int read()
{
	int x=0,f=1;char ch=getchar();
	while (ch<'0'||ch>'9'){if (ch=='-') f=-1;ch=getchar();}
	while (ch>='0'&&ch<='9'){x=x*10+ch-48;ch=getchar();}
	return x*f;
}

signed main(){
	string s;
	cin>>s;
	int cnt=0;
	for(int i=0;i<s.size();i++){
		switch (s[i]) {
			case '1':case'2':case'4':case'8':cnt++;
		}
		if(i>=4&&s[i-4]=='6'&&s[i-3]=='5'&&s[i-2]=='5'&&s[i-1]=='3'&&s[i]=='6')
		{
			cnt++;
			if(i+5<=s.size()&&s[i]=='6'&&s[i+1]=='5'&&s[i+2]=='5'&&s[i+3]=='3'&&s[i+4]=='6')i=i+5;
		}
	}
	cout<<cnt;
    return 0;
}