#include <iostream>
#include<string>
#include<fstream>

using namespace std;

int main()
{
    ifstream f("text.in");
    ofstream g("text.out");
    char txt[1000],txt2[1000],*p;
        long nr=0,k=0;


    f.getline(txt,1000);
    strcpy(txt2,txt);
    p=strtok(txt," .,;");
    while(p!=NULL)
    {
        k++;
        p=strtok(NULL," .,;");
    }
    p=strtok(txt2," .,;-!?");
    while(p!=NULL)
    {
        nr+=strlen(p);
        p=strtok(NULL, " .,;-!?");
    }
    g<<nr/k;
    f.close();
    g.close();
}