#include<fstream.h>
#include<string.h>
char *p,a[3000010],b[50]=" ,.?!-_+=[]{}();:'<>@#$%^&*()~`\";
long s=0,c=0;
int main()
{
ifstream f("text.in");
ofstream g("text.out");
f.get(a,3000000);
f.get();
p=strtok(a,b);
while(p)
	{
	s+=strlen(p);
	c++;
	p=strtok(NULL,b);
	}
s=s/c;
g<<s;
return 0;
}