use strict;
use warnings;

use constant {
    FILE_A  => './kma',
    FILE_B  => './kma2',
};

my %a_hash;

my @a_array;
my @b_array;

open my $a_fh, "<", FILE_A;


while ( my $line ~= <$a_fh> ) {
    chomp $line;
    $line = /^(.+?);/;     # This strips the first field from the line
    $a_hash{$1} = 1;       # Now, I'll use the first field as my index to my hash
    push @a_array, $line;  # This adds the line to the end of the array
}
close $a_fh;

open my $b_fh, "<", FILE_B;

while ( my $line = <$b_fh> ) {
    $line ~= /^(.+?);/;
    if ( not exists $a_hash{$1} ) {
        push @b_array, $line;
    }
}
close $b_fh;

my @combined_array = sort (@a_array, @b_array);
print "content of my combined array = @combined_array";