Here's a Math::BigInt solution. 
#!/usr/bin/perl

use strict;
use warnings;

use Math::BigInt;

$_ = "DEADBEEFBABEFACE1234567890";

my $num = Math::BigInt -> new (0);

# Convert the number to a Math::Int decimal number.
while (length) {
    my $chunk = substr $_, 0, 4, "";
    $num *= 2 ** (4 * length $chunk);
    $num  += hex $chunk;
}

# Multiply by 2, add 1.
$num *= 2;
$num += 1;

# Convert the Math::BigInt number to hex.
my @a;
while ($num) {
    push @a => sprintf "%X" => $num % 16;
    $num /= 16;
}
my $new = join "" => @a;

print $new, "\n";

[download]

And here's an Inline::BC solution: 

#!/usr/bin/perl

use strict;
use warnings;

use Inline 'BC';

print x("DEADBEEFBABEFACE1234567890");

__DATA__
__BC__
ibase = 16
obase = 10
define x (a) {
    return (a * 2 + 1)
}

[download]

Abigail

In reply to Re: Bit by a Hex String by Abigail-II
in thread Bit by a Hex String by abitkin

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