/// Craciun Catalin
///  Text
///   www.infoarena.ro/problema/text
#include <iostream>
#include <fstream>
using namespace std;
ifstream f("text.in");
ofstream g("text.out");

char t[5000000];
long lit=0; /// Numarul de litere
long cuv=0; /// Numarul de cuvinte
long rez; /// Rezultatul

void citire(){
    f.getline(t,5000000);
}

void parcurgere(){
    /// Parcurg sirul de caractere
    for (long i=0;i<strlen(t);i++){
        if ((t[i]>='a' && t[i]<='z')||(t[i]>='A' && t[i]<='Z')){
            lit++;
            if ((i==0) || ((t[i-1]<'a' || t[i-1]>'z')&&(t[i-1]<'A' || t[i-1]>'Z'))){
                cuv++;
            }
        }
    }

    rez=(lit/cuv)%10;
}

int main(){

    citire();
    parcurgere();
    g<<rez;
    g.close();

    return 0;
}