MAYBE
0.08/0.18	MAYBE
0.08/0.18	
0.08/0.18	Problem:
0.08/0.18	 del(.(x,.(y,z))) -> f(=(x,y),x,y,z)
0.08/0.18	 f(true(),x,y,z) -> del(.(y,z))
0.08/0.18	 f(false(),x,y,z) -> .(x,del(.(y,z)))
0.08/0.18	 =(nil(),nil()) -> true()
0.08/0.18	 =(.(x,y),nil()) -> false()
0.08/0.18	 =(nil(),.(y,z)) -> false()
0.08/0.18	 =(.(x,y),.(u(),v())) -> and(=(x,u()),=(y,v()))
0.08/0.18	
0.08/0.18	Proof:
0.08/0.18	 Open
0.08/0.18	EOF