my @nc;
my %seen;
while (<$fh>) {
    chomp;
    push @nc, $_ if !$seen{$_}++;
}

[download]

Or if your input is guaranteed to be sorted, 

my @nc;
my $last;
while (<$fh>) {
    chomp;
    push @nc, $last = $_ if !defined($last) || $last ne $_;
}

[download]

In reply to Re: Capturing Unique Data by ikegami
in thread Capturing Unique Data by donkost

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