#include <bits/stdc++.h>
using namespace std;
ifstream ci("text.in");
ofstream cou("text.out");
string s;
int nrcuv,nrlitere;

int main()
{
  while(ci>>s){
    for(int i=0;i<=s.length()-1;i++ ){



        if((int('a')<=int(s[i])&&int(s[i])<=int('z'))||(int('A')<=int(s[i])&&int(s[i])<=int('Z') ) ){

           while(('a'<=s[i]&&s[i]<='z')||('A'<=s[i]&&s[i]<='Z' )){
            i++;
            nrlitere++;
           }

           nrcuv++;
        }



    }

  }

cou<<nrlitere/nrcuv;

}