my @array_code= qw(WE4321 PP7654 8973 7865 TT3422);

my %code_numbers = (
  "4321" =>"XX",
  "7654" => "BB",
  "8973" => ""
);

foreach my $value (@array_code){
    my $nums = $value;
    $nums =~ s/\D//g;
    if(exists($code_numbers{$nums})){
        if($code_numbers{$nums} eq ''){
            print "$value\tIN\n";
        }else{
            print "$value\t$code_numbers{$nums}\n";
        }
    }

}
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