如何在Perl中存储数组或散列中的重复值？

Question

让我们这很容易.我想要的是:

@array = qw/one two one/;
my @duplicates = duplicate(@array);
print "@duplicates"; # This should now print 'one'.

如何打印数组/哈希的重复值？

Answer 1

sub duplicate {
    my @args = @_;
    my %items;
    for my $element(@args) {
        $items{$element}++;
    }
    return grep {$items{$_} > 1} keys %items;
}