This is what I have so far, I know it is a mess. I'm not quite sure if this was the best way to incorporate the test files, but I put them at the bottom under DATA.

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


my @files = shift
foreach my $file (@files) {
    open my $fh, '<', $file
        or die "Couldn't read '$file': $!";
    
    while (<$fh>) {
        my %names;
        my $name ;
        my $number;   
        
          $name = $1;
          $name = split(',', $files);
    };



__DATA1___
A12345,23
A22334,100
A22789,44
A10923,89

__DATA2___
A89224,88
A12345,99
A78663,100
A10923,89

Expected output: given 2 matches present and at least one in each file
A10923
A12345
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