#!/usr/bin/perl

use strict;
use warnings;

my $size = 18;
my $n = 10 ** $size;
my @number = 0;

my $binary = 1 . 0 x 8192;

for ( split //, $binary )
{
  my $carry = $_;
  for ( @number )
    {
    $_ += $_ + $carry;
    $carry = int $_ / $n;
    $_ %= $n;
    }
  $carry and push @number, $carry;
}
s/0+(?=.)// for my $decimal = join '', map sprintf('%0*d', $size, $_),
+ reverse @number;
print "$decimal\n";
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Are you running a 32-bit perl? It seems your sprintf has a problem with 18 digit numbers. Try changing $size to 8 or 9. (I don't have a 32-bit perl to test on.)

Also replace s/0+(?=.)// with s/^0+(?=.)//

THANK YOU! IT WORKS!!!! Yes, when I am on Windows, it is 32-bit.