#include<iostream.h>
#include<fstream.h>
#include<string.h>
#include<ctype.h>
ifstream f("text.in");
ofstream g("text.out");
int main()
{
	char s[256],*p,sep[50]=" `~!@#$%^&*()_+=-{}][:';<>?/.,";
	long long cuv=0,lit=0;
	while(f.get(s,255))
	{	p=strtok(s,sep);
	while(p)	
	{cuv++;
		lit+=strlen(p);
		p=strtok(NULL,sep);
	}}
	g<<lit/cuv;
		g.close();
		f.close();
}