#include <iostream>
#include <fstream>
#include <string.h>
using namespace std;
ifstream f("text.in");
ofstream g("text.out");
char sir[10001],*p;
int main()
{
    int nrcuv,nrlit;
    f.getline(sir,10001);
    nrcuv=0;
    nrlit=0;
    p=strtok(sir," ,.-!?");
    if(p!='\0')
    {
        nrcuv++;
        nrlit=nrlit+strlen(p);
    }
    while(p)
    {
        p=strtok(NULL," ,.-!?");
        if(p!='\0')
        {
            nrlit=nrlit+strlen(p);
            nrcuv++;
        }
    }
    g<<nrlit/nrcuv;
    return 0;
}