#include<fstream>
#include<cstring>
using namespace std;
ifstream in("text.in");
ofstream out("text.out");
int main(){
char s[1000000];
int litere=0,cuvinte=0,i,n;
in.get(s,100000);
in.get();
n=strlen(s);
for(i=0;i<n;i++){
	if((s[i]>='A' && s[i]<='Z') || (s[i]>='a' && s[i]<='z')){
		i++;litere++;
		while(i<n && ( (s[i]>='A' && s[i]<='Z') || (s[i]>='a' && s[i]<='z') ) ){
			i++;
			litere++;
			
		}
	cuvinte++;
	}
}
out<<litere/cuvinte;
}