#!/usr/bin/perl
use warnings;
use strict;

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

my %code_numbers = (
  "4321" =>"XX",
  "7654" => "BB",
  "8973" => ""
);
my $key;
my $len = $#array_code; 

for(my $i= 0; $i <= $len; $i++){
    $key = $array_code[$i];
    $key =~ s/\D//g;
    if (exists $code_numbers{$key}){
        my $val = $code_numbers{$key};
        if($val eq ''){
            print "Key:$key \t Value:$val \n";
            $code_numbers{$key} = "IN";
        }
        print "Key:$key \t Value:$code_numbers{$key} \n";
    }
}
exit;
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