You could examine $f2 with List::Uniq. 
#!/usr/bin/perl

use strict;
use warnings;
use List::Uniq qw(:all);
use Data::Dumper::Concise;

my $f2 = [ qw|a c d b e d a|];
my $uniq = uniq( {sort => 1}, $f2 );
print Dumper($uniq);

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In reply to Re: Perl sorting unique values by Khen1950fx
in thread Perl sorting unique values by pr09

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