use Bit::Vector;

my @probs =(0,0.1,0.53,0.51,0.59,0.67,0.2,0.04,0.05,0.56,0.89,0.75);

my $v = Bit::Vector->new(int @probs);
$v->Index_List_Store(grep { $probs[$_] > .5 } 0..$#probs);

for (my ($start, $min, $max) = 0; $start < $v->Size(); $start = $max + 2) {
	last unless ($min, $max) = $v->Interval_Scan_inc($start);
	print "$min $max\n";
}

##</code><code>##

2-5,9-11