in reply to Homework Golf
-p $_ x=65==map{97..ord lc}/./g
thanks to user oiskuu for the correction on the 97
This 'problem' popped into my head again last week with the thought that, unusually, I'd been an idiot. :) This beats even Grimy's 5 bit match (with the false positives) into a cocked hat. I think I win :D