module Stuff where


-- single line comments
{-  multiple line comments
filter test [] = []
filter test (a:as) 
  |test a = a: filter test as
  |not test a = filter test as
-}

filter test as = [ x | x <- as, test x]


data BinSearchTree a = Tree a (BinSearchTree  a)(BinSearchTree a) | Empty

inTree a Empty = False
inTree a (Tree b left right )
  | a == b = True
  | a < b = inTree a left
  | a > b = inTree b right

tree1 = (Tree 11 (Tree 5 (Tree 3 Empty Empty)  (Tree 7 Empty Empty))
           (Tree 25 (Tree 23 Empty Empty)  (Tree 37 Empty Empty)) ) 


evens = 0 : [2 + e | e <- evens]
nthEven n = evens!!n

fibs = 0 : 1 : [(a + b)| (a,b) <- zip fibs (tail fibs)]
fib n = fibs !! n