26 lines
772 B
Haskell
26 lines
772 B
Haskell
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main :: IO ()
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main = do
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instructions <- getContents
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let
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parsed = parseInstructions instructions
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location = navigate parsed
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solution1 = uncurry (*) location
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print solution1
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parseInstructions :: String -> [(Int, Int)]
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parseInstructions instructions =
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map parseLine (lines instructions)
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where
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parseLine line = case break (== ' ') line of
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("forward", distance) -> (read distance, 0)
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("down", distance) -> (0, read distance)
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("up", distance) -> (0, (-read distance))
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_ -> error "Invalid line"
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navigate :: [(Int, Int)] -> (Int, Int)
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navigate instructions =
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foldl1 sumTuples instructions
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where
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sumTuples :: (Int, Int) -> (Int, Int) -> (Int, Int)
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sumTuples (a, b) (c, d) = (a + c, b + d)
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