MAYBE
0.08/0.18	MAYBE
0.08/0.18	
0.08/0.18	Problem:
0.08/0.18	 double(0()) -> 0()
0.08/0.18	 double(s(x)) -> s(s(double(x)))
0.08/0.18	 del(x,nil()) -> nil()
0.08/0.18	 del(x,cons(y,xs)) -> if(eq(x,y),x,y,xs)
0.08/0.18	 if(true(),x,y,xs) -> xs
0.08/0.18	 if(false(),x,y,xs) -> cons(y,del(x,xs))
0.08/0.18	 eq(0(),0()) -> true()
0.08/0.18	 eq(0(),s(y)) -> false()
0.08/0.18	 eq(s(x),0()) -> false()
0.08/0.18	 eq(s(x),s(y)) -> eq(x,y)
0.08/0.18	 first(nil()) -> 0()
0.08/0.18	 first(cons(x,xs)) -> x
0.08/0.18	 doublelist(nil()) -> nil()
0.08/0.18	 doublelist(cons(x,xs)) -> cons(double(x),doublelist(del(first(cons(x,xs)),cons(x,xs))))
0.08/0.18	
0.08/0.18	Proof:
0.08/0.18	 Open
0.08/0.19	EOF