I have a utility function I often use for this sort of thing. See Below:

my(@numbers) = <DATA>;
chomp @number;
print join("\n", uniqStrings(@numbers));

sub uniqStrings
{
    my %temp = ();
    @temp{@_} = ();
    return keys %temp;
}

__DATA__
1236
3232
1236
4323
4323
[download]

That will actually run a little faster because the method used to remove duplicate numbers is pretty well optimized. Hope that helps.