#include<fstream>
using namespace std;
fstream in,out;
char s[1050007];
int main(){
	long i=0,c=0,l=0,t=0;
	in.open("text.in",ios::in);
	out.open("text.out",ios::out);
	in.getline(s,1050007,EOF);
	while(s[i]!=0){
		t=0;
		if(s[i]=='-'-0)
			++i;
		while((s[i]>='a'-0 && s[i]<='z'-0)||(s[i]>='A'-0 && s[i]<='Z'-0)){
			++t;
			++i;
		}
		if(t>0){
			l+=t;
			++c;
		}
		else
			++i;
	}
	if(c>0)
		out<<(l/c);
	else
		out<<"0";
	in.close();
	out.close();
	return 0;
}