#include<fstream.h>
ifstream f("text.in");
ofstream g("text.out");
int a[2000],i,ok,nr;
long s;
char c;
int main(){
i=1;ok=0;s=0;
while(!f.eof()){
    if(!f.eof()){
    c=f.get();
     if('a'<=c&&c<='z'||'A'<=c&&c<='Z')
       ok=1;nr=1;
	while('a'<=c&&c<='z'||'A'<=c&&c<='Z'){
	   c=f.get();
	      if('a'<=c&&c<='z'||'A'<=c&&c<='Z')
		   nr++;}
     if(ok==1){
	   ok=0;i++;
	   a[i]=nr;s=s+nr;}}}
g<<s/(i-1);
return 0;
}