module Trees where



--import Prelude(Int(..), Show(..))



data Nat = Zero | Succ Nat

    deriving (Show, Eq, Ord)



data Tree a = Leaf a | Branch (Tree a) a (Tree a)

    deriving Show



data TreeTwo b = Leaft b | Brancht (Tree b) (Tree b)

    deriving Show



treeOne = Branch (Branch (Leaf 14) 20 (Leaf 21)) 25 (Branch (Leaf 29) 37 (Branch (Leaf 43) 50 (Leaf 52)))

treeTwo = Brancht (Brancht (Leaft 14) (Leaft 21)) (Brancht (Leaft 29) (Brancht (Leaft 43) (Leaft 52)))



--переворот

reverseTree :: Tree a -> Tree a

reverseTree (Branch left value right) = (Branch (reverseTree right) value (reverseTree left))

reverseTree (Leaf value) = Leaf value



--глубина

depth :: Tree a -> Nat

depth (Leaf a) = Succ Zero

depth (Branch left value right) = Succ(max (depth left) (depth right))



--список

leaves :: Tree a -> [a]

leaves (Leaf a) = [a]

leaves (Branch left a right) = leaves left ++ leaves right