Dear Perlmonks,

If I have a hash with elements that are either a value (1) or undef is there a quick and simple way of counting the number of keys which are undef or defined (1) without iterating over the entire hash?

I'm probably exposing a deeply ignorant postion with my knowledge of hashes here, but it is a speed issue - the hashes represent states of DNA bases in a genome and the fastest solution is absolutely required.

Many thanks in advance,

Bukowski - aka Dan (dcs@black.hole-in-the.net)
"Coffee for the mind, Pizza for the body, Sushi for the soul" -Userfriendly

In reply to Counting keys with defined or undefined elements in a hash by Bukowski

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