#!/usr/bin/perl -w
use strict;

my %xlate = ('A' => 1000,
             'B' => 2000,
             'X' => 9999,
            );

while (<DATA>)
{
   chomp;
   foreach my $ltr (my @ltrs = split(//,$_))
   {
      print "$xlate{$ltr} " if  $xlate{$ltr};
      print "$ltr "         if !$xlate{$ltr};
   }
   print "\n";   
}
__END__
Prints:
1000 1000 2000 2000 C C 
1000 C 2000 9999 1000 

__DATA__
AABBCC
ACBXA