#include <bits/stdc++.h>

int main() {
    std::ifstream fin("text.in");
    std::ofstream fout("text.out");

    std::string line;
    int total_len = 0;
    int num_words = 0;
    while (std::getline(fin, line)) {
        bool isWord = false;
        int len = 0;
        for (int i = 0; i < line.size(); ++i) {
            if ((line[i] >= 'a' && line[i] <= 'z') || (line[i] >= 'A' && line[i] <= 'Z')) {
                isWord = true;
                len++;
            } else {
                if (isWord) {
                    total_len += len;
                    len = 0;
                    num_words += 1;
                    isWord = false;
                }
            }
        }

        if (isWord) {
            total_len += len;
            len = 0;
            num_words += 1;
            isWord = false;
        }
        
    }

    int avg = total_len / num_words;
    fout << avg << "\n";

    fin.close();
    fout.close();

    return 0;
}