#include <stdio.h>
#include <stdlib.h>
#include <fstream>
#include <iostream>
using namespace std;

int ischar(char c)
{
    if(('A'<=c&&'Z'>=c)||('a'<=c&&'z'>=c))
        return 1;
    return 0;
}

int main()
{

    char c1=' ', c2='\0';
    ifstream f("text.in");
    ofstream g("text.out");
    long int sum=0, nc=0;
    while(!f.eof())
    {
        c2=f.get();
        if(ischar(c2)==1)
            sum++;
        else
            if(ischar(c1)==1)
                nc++;
        c1=c2;
    }
    g<<sum/nc;
    return 0;
}