#include <fstream>
using namespace std;
ifstream fin ("text.in");
ofstream fout("text.out");
char c,b;
int nr_litere=0,nr_cuvinte=0;
int main()
{
    fin>>c;
    b='.';
    while (b!=EOF)
    {
        fin>>b;
        if ((c>64&&c<91)||(c>96&&c<123))
        {
            ++nr_litere;
            if (b<=64||(b>=91&&b<=96)||b>=123)
                ++nr_cuvinte;
        }
        c=b;
            }
        fout<<nr_litere/nr_cuvinte;
        return 0;
}