#include <fstream>
#include <cstring>
using namespace std;
ifstream f("text.in");
ofstream g("text.out");
char c;
int nrcuvinte,nrcaractere,este,caracter;
int main()
{
    este=1;
    while(f.get(c))
    {if(c>='a'&&c<='z'||c>='A'&&c<='Z')
        {if(este==1)nrcuvinte++;
         este=0;
         nrcaractere++;
         caracter=1;
        }
     else if(c!='-')este=1;

     if(caracter==0&&strchr(",-?!;':",c)){nrcuvinte++;caracter=0;}

    }
    g<<nrcaractere/nrcuvinte;

    return 0;
}