#include<fstream>
#include<cstring>
using namespace std;
ifstream f ("text.in");
ofstream g ("text.out");
int n,nr,S,i;
char a[1000],y[1000],x[1000],*q;
int main ()
{   f.getline (x,10000);
strcpy (y,x);
    for (i=0;i<strlen(x);i++)
	{   if (x[i]>='A' && x[i]<='Z' || x[i]>='a' && x[i]<='z')
			{strcpy (x+i,x+i+1);
		i--;}
	}

   q=strtok(y,x);
	while (q)
    {   S=S+strlen(q);
		nr++;
		q=strtok(NULL," .,?!");
	}
	g<<S/nr;
}