You can use grep. 

my (%a, %b);
@a{@a} = ();
@b{@b} = ();
@a = grep {exists $b{$_}} @a;
@b = grep {exists $a{$_}} @b;

[download]
Now @a and @b should be equal, containing only the common elements.

Added - fixed missing curlies, tlm++.

After Compline,
Zaxo

In reply to Re: Further question on removing elements from arrays by Zaxo
in thread Further question on removing elements from arrays by sandrider

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