my %lookup = map { $_ => 1 << (ord($_) - ord('A')) } 'A'..'Z';

my $c = 'ABCHI';

my $bitmap = 0;
$bitmap |= $lookup{$_} for $c =~ /(.)/g;

print('A'..'Z', "\n");
print(scalar(reverse(sprintf("%26b", $bitmap))), "\n");

##</code><code>##

ABCDEFGHIJKLMNOPQRSTUVWXYZ
111000011

##</code><code>##

my @powers = map { 1 << $_ } 0..25;

my $c = 'ABCHI';

my $bitmap = 0;
$bitmap |= $powers[ord($_)-ord('A')] for $c =~ /(.)/g;

print('A'..'Z', "\n");
print(scalar(reverse(sprintf("%26b", $bitmap))), "\n");