use strict;
use warnings;
use List::Compare;

my @symbol = (
   [ 'a', 'b', 'c' ],
   [ 'a', 'b', 'c'  ],
   [ 'a', 'b', 'c'  ],
   [ 'c', 'd', 'e'  ],
);

my $lCmp = List::Compare->new(@symbol);
my @unique = $lCmp->get_symmetric_difference ();
my @union =$lCmp->get_union ();

print "Unique: @unique\n";
print "Union: @union\n";
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Prints:

Unique: d e
Union: a b c d e
[download]