# include <fstream>
# include <cstdio>

using namespace std;

int nr1, nrcuv, nrlit;
char x;

bool check()
{
    if ( ( x >= 'A' && x <= 'Z' ) || ( x >= 'a' && x <= 'z' ) ) return true;
    return false;
}

int main ()

{
    fstream f("text.in");
    freopen ("text.out","w",stdout);

    while (f.get(x))
    {
        if (check() == true) nr1++;
        else
        {
            if (nr1) nrcuv++;
            nrlit += nr1;
            nr1 = 0;
        }
    }

    printf("%d\n", nrlit / nrcuv);

    return 0;
}