const litere=['a'..'z','A'..'Z'];
var c:char;
    k,con,s:integer;

begin
k:=0;
con:=0;
s:=0;
  assign(input,'text.in');  reset(input);
  assign(output,'text.out'); rewrite(output);
  while not eof do begin
   read(c);
   if c in litere then begin
             inc(con);
             if eof then begin s:=s+con; if con>0 then inc(k); end;
                       end
                  else begin s:=s+con; if con>0 then inc(k); con:=0; end;
   end;
   if k=0 then write('0') else
   write(s div k);
   readln;
   close(input); close(output);
   end.