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

using namespace std;

char cuv[1200000];
int lim,nrcuvinte,nrlitere,i;

int main()
{
    ifstream f ("text.in");
    ofstream g ("text.out");
    while(!f.eof())
    {
        f.getline(cuv,1200000);
        lim=strlen(cuv);
        for(i=0;i<lim;i++){
            if(isalpha(cuv[i])){
                 nrcuvinte++;
                 while(isalpha(cuv[i])){
                    nrlitere++;
                    i++;
                 }
            }
        }
    }
    g<<nrlitere/nrcuvinte;
    return 0;
}