program llll;
var f,g:text;
    c:char;
    nr,sum:longint;
begin
  assign(f,'text.in');
  reset(f);
  assign(g,'text.out');
  rewrite(g);
  nr:=0;
  sum:=0;
  while not eoln(f) do
    begin
      read(f,c);
      if (('a'<=c)and(c<='z'))or(('A'<=c)and(c<='Z')) then begin
                                                             sum:=sum+1;
                                                             nr:=nr+1;

      while ((('a'<=c)and(c<='z'))or(('A'<=c)and(c<='Z')))and(not eoln(f)) do begin
                                                                             read(f,c);
                                                                             if (('a'<=c)and(c<='z'))or(('A'<=c)and(c<='Z'))
                                                                              then sum:=sum+1
                                                                             end;
                                                            end;
    end;
    close(f);
    write(g,sum div nr);
    close(g);

end.