Refinement of emazep's: 
sub dani_l {
  my $s = shift;

  substr($s, $_ - 1, 2) =~ tr/1// == 1 or return 0 for @_;
  return 1;
}

[download]

In reply to Re: Re: fast bit twiddling by dani_l
in thread fast bit twiddling by spurperl

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