or, for slightly better performance (IIRC), ditch map in void context, and use 

$counts{$_}++ for @test;

[download]
or (for us antediluvian 5.004 types) 
for (@test) {$counts{$_}++}

[download]

I was hoping there was a Schwartzian Transform analog for this, just for the fun of running the whole thing into one line, but I can't come up with one.

Update:
No sooner posted than obsolete... 

@redundant = grep {++$counts{$_} > 1} @test;

[download]
Oops! 
@redundant = grep {++$counts{$_}==2} @test;

[download]
and a pox on foolish monks who post without full testing...


If God had meant us to fly, he would *never* have give us the railroads.
    --Michael Flanders

In reply to Re: Re: Finding Redundant values in arrays by ChemBoy
in thread Finding Redundant values in arrays by Anonymous Monk

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