For readibility & ease-of-use I like Set::Array. It has a wealth of set operation, including the one you're looking for:
use Set::Array;
...
my $set_a = Set::Array->new(@a);
my $set_b = Set::Array->new(@b);
my @c = $set_a->difference(@set_b);

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In reply to Re: Need to Create an Array of Differences by Anonymous Monk
in thread Need to Create an Array of Differences by scottj

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