What is the most efficient way to shift that 1 to the other end so I can compare the value to 1 instead of using this horrible regex. Or is there a quicker way?

I might try table lookup. 

sub is_power_of_2 {
      my $n = shift;
      1 == grep { $_ == $n } ( 1 2 4 8 ... )
  }

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In reply to Re: How can I tell if a number is a power of 2? by dws
in thread How can I tell if a number is a power of 2? by larryk

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