Program texte;
   var litere,simboluri:set of char;
       s:string;
       ch:char;
       suma,cuvinte,j:longint;
       f:text;
begin
  assign(f,'text.in'); reset(F); read(f,ch);
  litere:=['a'..'z','A'..'Z']; simboluri:=[chr(1)..chr(127)]-litere;
  s:=''; suma:=0; cuvinte:=0;
  while not eof(f) do begin
       while ch in simboluri do read(f,ch);
       while ch in litere do
                          begin
                            s:=s+ch;
                            read(f,ch);
                          end;
       if length(s)>0 then
                        begin
                          suma:=suma+length(s);
                          inc(cuvinte);
                          s:='';
                        end;
       end;
    close(f); assign(f,'text.out'); rewrite(f);
    writeln(f,suma div cuvinte); close(f);
end.