Another way: 
use warnings;
use strict;

my %seen;
print sort grep !$seen{$_}++, <DATA>
__DATA__
c
c
b
c
b
b
a
c
a
b

[download]
Caution: Contents may have been coded under pressure.

In reply to Re: a way to do 'sort|uniq' by Roy Johnson
in thread a way to do 'sort|uniq' by jch341277

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