99 questions/Solutions/15: Difference between revisions
< 99 questions | Solutions
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(added solution using list monad) |
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repli :: [a] -> Int -> [a] | repli :: [a] -> Int -> [a] | ||
repli xs n = concatMap (take n . repeat) xs | repli xs n = concatMap (take n . repeat) xs | ||
</haskell> | |||
or, using the list monad: | |||
<haskell> | |||
repli :: [a] -> Int -> [a] | |||
repli xs n = xs >>= replicate n | |||
</haskell> | </haskell> |
Revision as of 14:21, 5 August 2011
(**) Replicate the elements of a list a given number of times.
repli :: [a] -> Int -> [a]
repli xs n = concatMap (replicate n) xs
or, in Pointfree style:
repli = flip $ concatMap . replicate
alternatively, without using the replicate
function:
repli :: [a] -> Int -> [a]
repli xs n = concatMap (take n . repeat) xs
or, using the list monad:
repli :: [a] -> Int -> [a]
repli xs n = xs >>= replicate n