//
//  main.cpp
//  Alex
//
//  Created by Hurjui Alexandru Mihai on 02/11/2018.
//  Copyright © 2019 Hurjui Alexandru Mihai. All rights reserved.
//

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

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

int main()
{
    string s = {}, x;
    char *c, a[1000001] = {};
    int l = 0, nr = 0, i;
    getline(fin, x);
    for (i = 32; i<128; i++)
        if (!isalpha(char(i)))
            s.push_back(char(i));
    strcpy(a, x.c_str());
    c = strtok(a, s.c_str());
    while (c!=NULL)
    {
        nr++;
        l = l + strlen(c);
        c = strtok(NULL, s.c_str());
    }
    fout<<l/nr;
    return 0;
}