#include <iostream>
#include <fstream>
#include <string>
#include <cstring>
using namespace std;

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

int returnWordsNumber(string line, int &totalLetters) {
	int length = line.size();
	int hasWord = 0;
	int numbersOfWords = 0;
	for (int i = 0; i < length; ++i) {
		if (isLetter(line[i]) && hasWord == 0) {
			hasWord = 1;
			++totalLetters;
		} else if (isLetter(line[i]) && hasWord == 1) {
			++totalLetters;
		} else if (!isLetter(line[i]) && hasWord == 1) {
			++numbersOfWords;
			hasWord = 0;
		}
	}
	if (hasWord == 1) {
		++numbersOfWords;
	}
	return numbersOfWords;
}

int main() {
    ifstream fin("text.in");
    ofstream fout("text.out");
	string line;
	int totalLetters = 0;
	getline(fin, line);
	fin.close();
	returnWordsNumber(line, totalLetters);
	fout << totalLetters / returnWordsNumber(line, totalLetters);
	fout.close();
	return 0;
}