-- This is a source code template for Curry programs.

data Tree a = Empty | Node a (Tree a) (Tree a) deriving (Show)

tree = Node 10 Empty Empty

Insert :: (Ord a) => a -> Tree a -> Tree a
Insert x Empty = Node x Empty Empty
Insert x (Node y left right) | x == y = (Node y left right)
                             | x < y = Node y (Insert x left) right
                             | x > y = Node y left (Insert x right)
                             
Contains :: (Ord a) => a -> Tree a -> Bool
Contains x Empty = False
Contains x (Node y left right) | x == y = True
                               | x < y = Contains x left
                               | x > y = Contains x right


tree2 = Insert 9 (Insert 12 (Insert 13 tree))

Remove2 x (Node x Empty Empty) = Empty
Remove2 x (Node x left Empty) = left
Remove2 x (Node x Empty right) = right

--Remove :: (Ord a) => a -> Tree a -> Tree a
Remove x Empty = Empty
Remove x (Node y left right) | x == y = Remove2 x (Node y left right)
                             | x < y = (Node y (Remove x left) right)
                             | x > y = (Node y left (Remove x right)) 


main = Contains 13 tree2-- put here the main expression of your program