#include <fstream>
#include <iostream>

using namespace std;

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

int main()
{
    int ctcuvinte=0,ctlitere=0;
    char caractercrt,caracterprec;

    fin.get(caractercrt);
    if((caractercrt>='a' && caractercrt<='z') || (caractercrt>='A' && caractercrt<='Z'))
    {
        ctlitere++;caracterprec=ctlitere;
    }
    while(!fin.eof())
    {

        if((caractercrt>='a' && caractercrt<='z') || (caractercrt>='A' && caractercrt<='Z'))
        {
            ctlitere++;caracterprec=caractercrt;
        }
        else
        {
            if((caracterprec>='a' && caracterprec<='z') || (caracterprec>='A' && caracterprec<='Z'))
                ctcuvinte++;
            caracterprec=caractercrt;
        }
        fin.get(caractercrt);
    }
    fout<<ctlitere/ctcuvinte;
    return 0;
}