#include <string.h>
#include <fstream>

using namespace std;
const int INT=1000000;
char s[INT];
int caractere=0;
int cuvinte=0;

ifstream in("text.in");
ofstream out("text.out");
bool litera(char s){
    if(('a'<=s && s<='z') || ('A'<=s && s<='Z')) return 1;
    return 0;
}
int main(){
while(in.get(s,INT)){
    for(int i=0;s[i]!=0;i++)
        if(litera(s[i])==1){
            caractere++; // numarul de caractere creste.
            if(i==0 || litera(s[i-1])==0){ // daca este inceputul unui cuvant.
                cuvinte++;
            }
        }
    }
out<<caractere/cuvinte;
in.close();
out.close();
return 0;
}