Difference between revisions of "99 questions/Solutions/1"
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Luc4sdreyer (talk | contribs) m (Added another answer: myLast''''') |
(Added base case to myLast) |
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<haskell> |
<haskell> |
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myLast :: [a] -> a |
myLast :: [a] -> a |
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+ | myLast [] = error "No end for empty lists!" |
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myLast [x] = x |
myLast [x] = x |
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myLast (_:xs) = myLast xs |
myLast (_:xs) = myLast xs |
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The <hask>Prelude</hask> also provides the function <hask>last</hask>. |
The <hask>Prelude</hask> also provides the function <hask>last</hask>. |
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+ | |||
+ | [[Category:Programming exercise spoilers]] |
Latest revision as of 13:52, 25 August 2014
(*) Find the last element of a list.
myLast :: [a] -> a
myLast [] = error "No end for empty lists!"
myLast [x] = x
myLast (_:xs) = myLast xs
myLast' = foldr1 (const id)
-- Prelude> const 1 2
-- 1
-- Prelude> (flip const) 1 2
-- 2
myLast'' = foldr1 (flip const)
myLast''' = head . reverse
myLast'''' = foldl1 (curry snd)
myLast''''' [] = error "No end for empty lists!"
myLast''''' x = x !! (length x -1)
The Prelude
also provides the function last
.