#include <iostream>
#include <fstream>
#include <cctype>

using namespace std;

ifstream fin("text.in");
ofstream fout("text.out");

int main() {
    string line;
    getline(fin, line);
    
    int len = 0, lentot = 0, cnt = 0;
    for (char ch: line)
        if (isalpha(ch))
            len++;
        else if (len > 0) {
            cnt++;
            lentot += len;
            len = 0;
        }
    if (len > 0) {
        cnt++;
        lentot += len;
    }
    fout << lentot/cnt << '\n';

    return 0;
}