26 lines
625 B
Haskell
26 lines
625 B
Haskell
getMax :: [Int] -> Maybe Int
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getMax [] = Nothing
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getMax x = Just (maximum x)
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reciprocal :: (Eq a, Fractional a) => a -> Maybe a
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reciprocal 0 = Nothing
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reciprocal x = Just (1/x)
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rectangleArea :: Int -> Int -> Either String Int
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rectangleArea x y
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| x < 0 = Left "Width is not positive"
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| y < 0 = Left "Height is not positive"
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| otherwise = Right (x * y)
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main :: IO ()
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main = do
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print $ getMax []
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print $ getMax [99,12,37]
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print $ getMax [-99,-12,-37]
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print $ reciprocal 4
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print $ reciprocal 2
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print $ reciprocal 0
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print $ rectangleArea 5 10
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print $ rectangleArea (-5) 10
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print $ rectangleArea 5 (-10)
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