If you mean, "How can I display an array of the unique elements of an array that contains some repeated elements", this may serve your purpose:

my @ary = qw(a b c d d e b d);
my %hsh;
undef @hsh{@ary};
my @ary2 = keys %hsh;
print "@ary2\n";
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The key here is:  undef @hsh{@ary};  which is a hash slice. The hash slice is an lvalue (that is, it is assignable). The undef is associative for each element of the slice. The effect of this is to establish a key in the hash corresponding to each array element. Except that duplicate keys just write over each other. Each key has a corresponding value of undef. Then, on the next line we just extract the (now unique) keys into a new array.