#!/usr/bin/perl

use warnings;
use strict;

open PATIENTS, "PATIENT_TABLE_UPLOAD.csv"
    or die "problem opening PATIENTS file\n";

my @ACFUnumbers;
my @duplicateACFUS;

while (<PATIENTS>) {

    my @fields  = split /,/;
    my $ACFU    = $fields[1];
    push @ACFUnumbers, $ACFU;

} #end while

foreach my $outerACFU (@ACFUnumbers) {

    $outerACFU = shift;

    foreach my $innerACFU (@ACFUnumbers) {
        unless (!defined($innerACFU) or ($innerACFU =~ /^\s$/)) {
            if (defined ($outerACFU) and defined($innerACFU)) {
                push @duplicateACFUS, $outerACFU
                    if ($outerACFU eq $innerACFU);
            } #end if

        } #end unless
    } #end inner foreach
} #end foreach

print "$_\n" foreach @duplicateACFUS;
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