#include <fstream>
#include <cstring>
#include <cctype>
using namespace std;
ifstream fin("text.in");
ofstream fout("text.out");
char x[10000];
int main()
{
    int i,nrc=0,nrl=0,l,j,ok;
    while (fin >> x)
    {
        for (i=0; i<strlen(x); ++i)
        {
            if (isalpha(x[i]))
            {
                ++nrl;
            }
        }
        i=0;
        while (i<strlen(x))
        {
            ok=0;
            if (isalpha(x[i]))
            {
                l=1;
                for (j=i+1; j<strlen(x); ++j)
                {
                    if (!isalpha(x[j])) break;
                    ++l;
                }
                ++nrc;
                i = i+l;
                ok=1;
            }
            if (!ok) ++i;
        }
    }
    fout << nrl / nrc << "\n";
    return 0;
}