Have you consider doing a line-by-line comparison, if you have large files you might end up consuming too much memory for storing an array with the contents. Here's an example
use strict;
use warnings;
open my $fh1, '<', 'file1';
open my $fh2, '<', 'file2';
while ( defined( my $line1 = <$fh1> ) and defined( my $line2 = <$fh2>
+) ) {
chomp($line1);
chomp($line2);
my @values1 = split( ',', $line1 );
my @values2 = split( ',', $line2 );
print "$values2[4]\n"
if ( $values1[0] eq $values2[1]
and $values1[1] eq $values2[2]
and $values1[2] eq $values2[3] );
}