MAYBE
219.78/55.68	MAYBE
219.78/55.68	
219.78/55.68	Problem:
219.78/55.68	 f(x,a(b(y))) -> f(a(b(b(x))),y)
219.78/55.68	 f(a(x),y) -> f(x,a(y))
219.78/55.68	 f(b(x),y) -> f(x,b(y))
219.78/55.68	
219.78/55.68	Proof:
219.78/55.68	 Open
219.78/55.69	EOF