Just one comment more.
In perlfaq4 you have a chunk of code to evaluate union, intersection a difference from two arrays.
"How do I compute the difference of two arrays? How do I compute the intersection of two arrays?"
You can see question/answer here 
perldoc -q intersection

[download]

Hopes 
perl -le '$_=$,=q,\,@4O,,s,^$,$\,,s,s,^,b9,s,$_^=q,$\^-]!,,print'

[download]

In reply to Re: Union of arrays by hopes
in thread Union of arrays by Ananda

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