14 lines
443 B
Haskell
14 lines
443 B
Haskell
data Tree a = Empty | Branch a (Tree a) (Tree a)
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deriving (Show, Eq)
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hbalTree :: a -> Int -> [Tree a]
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hbalTree _ 0 = [Empty]
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hbalTree x 1 = [Branch x Empty Empty]
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hbalTree x n =
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[Branch x l r | l <- minustwocase, r <- minusonecase]
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++ [Branch x l r | l <- minusonecase, r <- minusonecase]
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++ [Branch x l r | l <- minusonecase, r <- minustwocase]
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where
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minusonecase = hbalTree x (n - 1)
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minustwocase = hbalTree x (n - 2)
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