#include <iostream>
#include <fstream>
#include <cstring>
#define nmax 1048580
using namespace std;
int main()
{
    const char ctdel[100]="`1234567890-=[];\\\"/,\'!@#$%^&*()_+{}:|<>? ~";
    ifstream f("text.in");
    ofstream g("text.out");
    char s[nmax],*res;
    int c=0,suma=0;
    f.get(s,nmax);
    res=strtok(s,ctdel);
    while(res != NULL)
    {
        c++;
        suma+=strlen(res);
        res=strtok(NULL,ctdel);
    }
    g<<suma/c;
    return 0;
}