#include <iostream>
#include <fstream>
using namespace std;

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

int main()
{
    string s;
    int nrCuv=0,nrLitere=0;
    char caract;
    while(fin>>s)
    {
        caract='#';
        for (int i=0; i<s.length(); i++)
        {
            if((s[i]>='a' && s[i]<='z')||(s[i]>='A' && s[i]<='Z'))
            {
                nrLitere++;
                if((caract<'a' || caract>'z') && (caract<'A' || caract>'Z'))
                {
                    nrCuv++;
                }
            }
            caract=s[i];
        }
    }
    fout<<nrLitere/nrCuv;





    fin.close();
    fout.close();
    return 0;
}