return grep { $u{ $_ } ? ( $u{ $_ }-- , $_ ) : () } split //, $str2;

[download]
Better written as: 
return grep --$u{ $_ } >= 0, split //, $str2;

[download]

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to •Re: Unique List of Common Characters Between Two Strings by merlyn
in thread Unique List of Common Characters Between Two Strings by Limbic~Region

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