#include <fstream>

using namespace std;

ifstream f("text.in");
ofstream g("text.out");

void text()
{
    char c;

    int litere = 0,cuvinte = 0;

    while(f>>c)
    {
        if((c >= 65 && c <= 90) || (c >= 97 && c <= 122))litere++;
        else
        if(c == ' ' || c == ',')
        cuvinte++;
    }

    g<<litere/cuvinte<<'\n';

}
int main()
{
    text();

    g.close();

    return 0;
}