27 lines
718 B
Haskell
27 lines
718 B
Haskell
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module Homework.Ch01.Hanoi where
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import qualified Data.HashMap.Strict as HashMap
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newtype Peg = Peg ()
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data Move = Move {moveFrom :: String, moveTo :: String} deriving (Eq, Show)
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data Disc = Disc {discSize :: Int}
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hanoi :: Int -> String -> String -> String -> Either String [Move]
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hanoi numDisks pegLabelA pegLabelB pegLabelC =
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let _pegs =
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HashMap.fromList
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[ (pegLabelA, fillPegWithDiscs),
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(pegLabelB, []),
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(pegLabelC, [])
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]
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in Right
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[ Move "a" "c",
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Move "a" "b",
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Move "c" "b"
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]
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where
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fillPegWithDiscs :: [Disc]
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fillPegWithDiscs = Disc <$> [1 .. numDisks] -- start here: make sure this is initialized correctly
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