sub RDup { my %unique; $unique{lc($_)} = $_ foreach @_; return sort values %unique; } my @unique; foreach $d (@dllExeLines) { if ($d =~ /\Q$serviceName/) { foreach $f (split(/,/, $d)) { if ($f =~ /\Q$dll/i) { push @unique, $dll; } } } } @unique = RDup(@unique);