add x y = x + y

succc = add 1

poww(0) = 1
poww(n) = 2 * poww(n-1)

lll([]) = 0
lll(x:xs) = 1 + lll(xs)

selectEven xs = [ x | x<-xs , even x ]

mxx(a,0) = a
mxx(0,b) = b
mxx(a,b) = 1 + mxx(a-1,b-1)

data Tree a = Null | Node a (Tree a) (Tree a)

depth Null = 0
depth(Node a b c) = 1 + mxx(depth(b),depth(c))

maxx Null = 0
maxx(Node a b c) = mxx(a,mxx(maxx(b),maxx(c)))

zuj([],b:bs) = []
zuj(a:as,[]) = []
zuj(a:as,b:bs) = (a,b):zuj(as,bs)

odzuj((a,b):as) = (a:rozzuja(as),b:rozzujb(as))

rozzuja([]) = []
rozzuja((c,d):ds) = c:rozzuja(ds)

rozzujb([]) = []
rozzujb((e,f):fs) = f:rozzujb(fs)

data Expr = Plus Expr Expr | Mult Expr Expr | Const Int

eva(Const a) = a
eva(Mult a b) = eva(a)*eva(b)
eva(Plus a b) = eva(a)+eva(b)

data Tre = Nil | Nod Int Tre Tre

data BVS a = Nul | Noe (BVS a) a (BVS a)

inor (Noe Nul d Nul) = d:[]
inor (Noe a b c) = inor(a)++b:inor(c)

pod((Noe a b c),d) = b < d
nad((Noe a b c),d) = b > d

lbvs((Noe Nul b Nul),d) | b < d = 1
		  	| b >= d = 0

lbvs((Noe a b c),d)   | pod(a,d) && (b < d) && pod(c,d) = 1 * lbvs(a,b) * rbvs(c,b)
		      | nad(a,d) || (b > d) || nad(c,d) = 0

rbvs((Noe Nul b Nul),d) | b > d = 1
		  	| b <= d = 0

rbvs((Noe a b c),d)   | nad(a,d) && (b > d) && nad(c,d) = 1 * lbvs(a,b) * rbvs(c,b)
		      | pod(a,d) || (b < d) || pod(c,d) = 0

isBVS (Noe Nul d Nul) = 1
isBVS (Noe a b c) = lbvs(a,b) * rbvs(c,b)