Just a reminder. You can prevent the addition of duplicates with Array::Unique. 
 use Array::Unique;
 tie @a, 'Array::Unique';

 @a = qw(a b c a d e f);
 push @a, qw(x b z);
 print "@a\n";          # a b c d e f x z

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In reply to Re: Howto Avoid Memory Problem in List::MoreUtils by codeacrobat
in thread Howto Avoid Memory Problem in List::MoreUtils by Anonymous Monk

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