Gray Code

[jdporter]

I needed a quick Gray code (specifically, a binary reflected Gray code), so I whipped this up. The one CPAN module which seems to implement Gray code, Math-PlanePath is wayy too heavy for my needs.

# returns a list of vectors of numbers in (0,1)
sub gray2;
sub gray2
{
    my($i) = @_;
    $i <= 1 and return([0],[1]);
    my @a = gray2($i-1);
    ( ( map { [ 0, @$_ ] } @a ), map { [ 1, @$_ ] } reverse @a )
}

my @a = gray2(3);
print "@$_\n" for @a;

[LanX]

at night all codes are gray... ;)

[Your Mother]

Except when it's dark on Tuesdays.

[LanX]

No that's yet another shade of gray. ...

[Old_Gray_Bear]

Fade to Black