#include <fstream>
#include <string>

using namespace std;
ifstream fin ("text.in");
ofstream fout ("text.out");
string cuv;
int nr_cuv, nr_litere;

int main()
{
    int i;
    while (fin >> cuv) {
        i = 0;
        bool lit = false, intrerupt = false;
        while (i < cuv.size()) {
            if ( ( cuv[i] >= 'A' && cuv[i] <= 'Z' ) || ( cuv[i] >= 'a' && cuv[i] <= 'z' ) ) {
                nr_litere++;
                lit = true;
                if (intrerupt == true) {
                    nr_cuv++;
                    intrerupt = false;
                }
            }
            else {
                intrerupt = true;
            }
            i++;
        }
        if (lit == true)
            nr_cuv++;
    }
    fout << nr_litere / nr_cuv;
    return 0;
}