sub bigint_to_bytearray {
  my $bigint = shift;
  my @bytes;
  while(1) {
    my ($q,$r) = $bigint->brsft(8);
    push(@bytes,$r+0);
    last if $q == 0;
    $bigint = Math::BigInt->new($q);
  }
  return @bytes;
}

##</code><code>##

## This is the one I would like to speed up
## The array looks something like (127,6,64,27,166,33 .... )
sub bytearray_to_bigint {
  my @array = @_;
  my $count = Math::BigInt->new('0');
  my $result = Math::BigInt->new('0');
  foreach my $a (@array) {
    $result += $a * (256**$count++);
  }
  return $result;
}