#include <iostream>
#include <fstream>
using namespace std;
ifstream f("text.in");
ofstream g("text.out");
string v;
int letters, words;

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

int main()
{
    while(1) {
        if(f.eof()) break;
        getline(f, v);
        for (int i=1; i<v.size(); i++) {
            if (isLetter(v[i]) && !isLetter(v[i-1])) words++;
            if (isLetter(v[i])) letters++;
        }
    }
    g<<letters/words<<"\n";
    return 0;
}