#include <fstream>

using namespace std;
ifstream cin("text.in");
ofstream cout("text.out");
bool litera(char x)
{
    if (x >= 'a' && x <= 'z' )
        return true;
    if ( x >= 'A' && x <= 'Z' )
        return true;
    return false;
}
int main()
{
    char x;
    int cate = 0, cnt = 0;
    cin.get(x);
    while (x != EOF && x != '\n')
    {
        if ( litera(x) == true )
        {

            while ( litera(x) == true )
            {
                ++cate;
                cin.get(x);
            }
            ++cnt;
        }
        cin.get(x);
    }
    cout << cate / cnt << endl;
    return 0;
}