MAYBE
0.09/0.18	MAYBE
0.09/0.18	
0.09/0.18	Problem:
0.09/0.18	 minus(x,0()) -> x
0.09/0.18	 minus(s(x),s(y)) -> minus(x,y)
0.09/0.18	 f(0()) -> s(0())
0.09/0.18	 f(s(x)) -> minus(s(x),g(f(x)))
0.09/0.18	 g(0()) -> 0()
0.09/0.18	 g(s(x)) -> minus(s(x),f(g(x)))
0.09/0.18	
0.09/0.18	Proof:
0.09/0.18	 Open
0.09/0.18	EOF