18 lines
456 B
Haskell
18 lines
456 B
Haskell
import Data.Maybe
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import Text.Read (readMaybe)
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getListFromString :: String -> Maybe [Integer]
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getListFromString str = readMaybe $ "[" ++ str ++ "]"
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askUser :: IO [Integer]
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askUser =
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putStrLn "Enter a list of numbers (sep. by commas):" >>
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getLine >>= \input ->
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let maybeList = getListFromString input in
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case maybeList of
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Just l -> return l
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Nothing -> askUser
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main :: IO ()
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main = askUser >>=
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\list -> print $ sum list
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