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Hanoi.hs

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+data Tower = First | Middle | Last deriving Show
+
+data Instruction = Move Tower Tower deriving Show
+
+-- show :: Instruction -> String
+-- show Move from to = "Moving " ++ show from ++ " to " ++ show to
+
+solve :: Tower -> Tower -> Tower -> Integer -> [Instruction]
+solve _ _ _ 0 = []
+solve from over to n = solve from to over (n - 1) ++ [Move from to] ++ solve over from to (n - 1)
+
+main :: IO ()
+main = let
+  solution = solve First Middle Last 4
+  in
+  print solution