#include <fstream>
using namespace std;

bool isLeter(char c);

int main()
{
    ifstream input("text.in");
    ofstream output("text.out");
    int words=0,word_size=0;
    char buff;

    while(!input.eof())
    {
       buff=input.get();
        if(isLeter(buff))
        {
            words++;
            while(isLeter(buff))
            {
                word_size++;
                 buff=input.get();
            }
        }
    }
    output<<word_size/words;
}

bool isLeter(char c)
{
    if((c>=65 && c<=90)||(c>=97 && c<=122))
        return true;
    else return false;
}