program text2;
{$APPTYPE CONSOLE}
uses
  SysUtils;
var fin,fout:text;
    i,j,lit,cuv:integer;
    ok:boolean;
    c:char;
begin
  assign(fin,'text.in');
  assign(fout,'text.out');
  reset(fin);
  rewrite(fout);
  cuv:=0;
  lit:=0;
  ok :=false;
  while not eof(fin) do
    begin
      i:=0;
      while not eoln(fin) do
        begin
          inc(i);
          read(fin,c);
          if (i= 1) and (c <>'-') then inc(cuv);
          case c of
            ' ':inc(cuv);
            '-':if i > 2 then inc(cuv);
{            '!':
              begin
                inc(cuv);
                j:=i;
                ok:=true;
              end;
            '.':
              Begin
                inc(cuv);
                j:=i;
                ok:=true;
              End;
            '?':
              Begin
                inc(cuv);
                j:=i;
                ok:=true;
              End;
            ':':inc(cuv);
            '_':inc(cuv); }
            '''':inc(cuv);
            '"':if i < 2 then inc(cuv);
            'a'..'z':inc(lit);
            'A'..'Z':inc(lit);
            '0'..'9':inc(lit);
          end;
        end;
      readln(fin);
    end;
  if j <> i then ok :=false;
  if ok then dec(cuv);
  writeln(fout,lit div cuv);
//  writeln(fout,lit div cuv,'   ',lit,'   ',cuv);
  close(fout);
end.