MAYBE
23.93/10.19	MAYBE
23.93/10.19	
23.93/10.19	Problem:
23.93/10.19	 f(f(a(),x),y) -> f(f(x,f(a(),y)),a())
23.93/10.19	
23.93/10.19	Proof:
23.93/10.19	 Open
23.93/10.19	EOF