Difference between revisions of "99 questions/Solutions/15"
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(added solution using list monad) |
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| Line 15: | Line 15: | ||
repli :: [a] -> Int -> [a] |
repli :: [a] -> Int -> [a] |
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repli xs n = concatMap (take n . repeat) xs |
repli xs n = concatMap (take n . repeat) xs |
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| + | </haskell> |
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| + | |||
| + | or, using the list monad: |
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| + | <haskell> |
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| + | repli :: [a] -> Int -> [a] |
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| + | repli xs n = xs >>= replicate n |
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</haskell> |
</haskell> |
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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