# for those times when Perl's built-in sort is just too fast

use strict;

my @data = qw(7 6 5 4 3 2 1 0) ;

rpsort(\@data);
print "$_\t" foreach (@data);

exit;

# a random permutation sort
# ref. Perl Cookbook recipe 4.17 for the shuffle

sub rpsort {
	my $list = shift;
	my ($k,$j);

try_again:
	for ($j = @$list; --$j; ) {
		$k = int rand($j+1);
		next if ($j == $k);
		@$list[$j, $k] = @$list[$k, $j];
	}

	for ($j = 0 ; $j < (@$list -1); $j++) {
		goto try_again if (@$list[$j] > @$list[$j+1]);
	}
}