#include <iostream>
#include <fstream>
#include <string>
#include <cstring>

using namespace std;

ifstream in("text.in");
ofstream out("text.out");

int main()
{
    string linie , caractere=" ./+-!?";
    int nrCuvinte=0 , nrLitere=0;

    while(!in.eof())
    {
        getline(in,linie);
        for(int i=0; i<linie.length(); ++i)
        {
            if( isalpha(linie[i]) )
                nrLitere++;
        }

        for(int i=0; i<linie.length(); ++i)
        {
            if( (isalpha(linie[i])) && (!isalpha(linie[i+1])))
                nrCuvinte++;
        }
    }

    out<<nrLitere/nrCuvinte;
    return 0;
}