#include<fstream.h>
#include<string.h>
ifstream f ("text.in");
ofstream g("text.out");
char sir[100000],*p;
int k,x;
int main ()
{f.get(sir,100000); f.get();
p=strtok(sir," .,;:'?></=-|+_1234567890");
while (p!=NULL)
{
	k+=strlen(p);
	x++;
	p=strtok(NULL," .,;:'?></=-|+_1234567890");
}
g<<k/x;
f.close();
g.close();
return 0;
}