#include <bits/stdc++.h>
using namespace std;
ifstream in("text.in");
ofstream out("text.out");
char s[1048578],
sep[]=" !#$%&'()*+,-./0123456789:;<=>?@[]\^_`{|}~";
;
int main()
{
sep[41]='"';
in.getline(s,1048576);
int cnt=0,nr=0;
char *p=strtok(s,sep);
while (p){
cnt++;
nr+=strlen(p);
p=strtok(NULL,sep);
}
out<<nr/cnt;
}