mmagm

data BinaryTree a = EmptyTree | Node a (BinaryTree a) (BinaryTree a)
     deriving (Show)

treeInsert :: Ord a => a -> BinaryTree a -> BinaryTree a
treeInsert el EmptyTree  = Node el EmptyTree EmptyTree
treeInsert el (Node a left right)
       | el == a = Node el left right
       | el < a = Node a (treeInsert el left) right
       | el > a = Node a left (treeInsert el right)