Use a hash to count each occurrance and then grep to get those that appear more than once.

my @a = qw/ 1 2 3 4 5 6 7 8 9 5 7 9 /;
my %h;
$h{$_}++ for @a;
my @dups = grep { $h{$_} > 1 } keys %h;
print "@dups\n";

[download]

Is one way.

In reply to Re: What is the best way to get just the duplicates from an array? by FunkyMonk
in thread What is the best way to get just the duplicates from an array? by wenD

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