#include <fstream>
#include <cmath>
#include <vector>
#include <algorithm>
#include <map>
#include <string>
#include <bitset>
#define pb(a) push_back(a)
using namespace std;

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

string a;
long long lungime_totala, cuvinte;

bool is_digit(char a){
    return a >= 'a' && a <= 'z' || a <= 'Z' && a >= 'A';
}

int main(){
    while(cin >> a){
        bool cuvant = false;
        for(int i = 0; i < a.size(); ++i){
            if(is_digit(a[i])){
                lungime_totala++;
                if(!cuvant){
                    cuvinte++;
                    cuvant = 1;
                }
            }
            else{
                cuvant = 0;
            }
        }
    }
    cout << lungime_totala / cuvinte;
    return 0;
}