99 questions/Solutions/2

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Revision as of 07:32, 15 November 2014 by Bitemyapp (talk | contribs) (Don't tell new people to write partial functions, come on.)
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(*) Find the last but one element of a list. 

myButLast :: [a] -> a
myButLast = last . init

myButLast' x = reverse x !! 1

myButLast'' [x,_]  = x
myButLast'' (_:xs) = myButLast'' xs

myButLast''' (x:(_:[])) = x
myButLast''' (_:xs) = myButLast''' xs

myButLast'''' = head . tail . reverse
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