program texti;
{$APPTYPE CONSOLE}
uses
  SysUtils;
var fin,fout:text;
    i,j,lit,cuv:integer;
    c:char;
begin
  assign(fin,'text.in');
  assign(fout,'text.out');
  reset(fin);
  rewrite(fout);
  cuv:=0;
  lit:=0;
  while not eof(fin) do
    begin
      while not eoln(fin) do
        begin
          read(fin,c);
          case c of
            ' ':inc(cuv);
            '-':inc(cuv);
            '!':inc(cuv);
            '.':inc(cuv);
            '?':inc(cuv);
            'a'..'z':inc(lit);
            'A'..'Z':inc(lit);
          end;
        end;
      readln(fin);
    end;
  writeln(fout,lit div cuv);
  close(fout);
end.