#include <fstream>

using namespace std;

ifstream fin("text.in");
ofstream fout("text.out");

int main()
{
    int nc=0,ntl=0,i;
    char c[100000];

    while(fin.getline(c,100000))
    {
        for(i = 0; c[i]; i++)
        {
            if ((c[i] >= 'a' && c[i] <= 'z') || (c[i] >= 'A' && c[i] <= 'Z'))
                ntl++;
        }

        i=0;

        while(c[i])
        {
            if ((c[i] >= 'a' && c[i] <= 'z') || (c[i] >= 'A' && c[i] <= 'Z'))
            {
                while ((c[i] >= 'a' && c[i] <= 'z') || (c[i] >= 'A' && c[i] <= 'Z'))
                {
                    i++;
                }
                nc++;
            }
            else
            {
                i++;
            }
        }

    }

    fout<<ntl/nc<<"\n";

    return 0;
}