#include <fstream>
#include <iostream>
#include <ctype.h>
using namespace std;
ofstream g("text.out");

int main()
{
  ifstream fin;

  fin.open("text.in", ios:: in);  
	
  char caracter_curent = '\0';
  int lungime_totala = 0, nr_cuvinte = 0;

  
  while (!fin.eof())
  {
	fin.get(caracter_curent);

    if (tolower(caracter_curent) >= 'a' && tolower(caracter_curent) <= 'z')	
	  ++lungime_totala;
    else if (lungime_totala != 0 && (caracter_curent == ' ' || caracter_curent == '-' || caracter_curent == '.' || caracter_curent == '!' || caracter_curent == '?'))
	  ++nr_cuvinte;  
  } 	   
  
  g << lungime_totala / nr_cuvinte;
  
  return 0;
}