Doing Decimal to Binary (was Re: [Nms-cgi-devel] FormMail.cgi CIDR)

[Jonathan S. <gel...@ge...>]

On Tue, 22 Jan 2002, Jonathan Stowe wrote:
> On Tue, 22 Jan 2002, Sam Smith wrote:
> >
> > It appears to be the %b formatting in the sprintf statements.
> >
> > Is there a 5.004 compatible equivalent?
> >
>
> I think that one used to do something funky with unpack :)
>

I had never really had the need to do this in Perl before - does this seem
like a reasonable way of doing it :

for my $foo ( 0 .. 65536 )
{
  my $I = 1;

  my $out = '';

  while($I <= $foo )
  {
    my $blah = $foo & $I ? 1 : 0;
    $out = $blah . $out;
    $I *= 2;
  }

  $out ||= '0';
  print "$foo : ", ($out eq sprintf("%b",$foo) ? 'good' : 'bad'  ),"\n";
}


You might have noticed I am not a mathematician :)

/J\
-- 
Jonathan Stowe                      |
<http://www.gellyfish.com>          |      This space for rent
                                    |