In the the three solutions that where posted, everyone uses 'exists $hash{key}' and a '$hash{key}=...' and to me these look like two look-ups in the hash to me. Is this efficient? Can this be more efficient?

Athanasius

++$count{$word} if exists $count{$word};

Tux

$cnt{$_}++ for grep { exists $cnt{$_} } m/(\w+)/g;

AnomalousMonk

exists $count{$_} and ++$count{$_} for $line =~ m{ $rx_word }xmsg;

In reply to Re: Count number of occurrences of a list of words in a file by Veltro
in thread Count number of occurrences of a list of words in a file by Azaghal

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