MAYBE
0.07/0.18	MAYBE
0.07/0.19	
0.07/0.19	Problem:
0.07/0.19	 purge(nil()) -> nil()
0.07/0.19	 purge(.(x,y)) -> .(x,purge(remove(x,y)))
0.07/0.19	 remove(x,nil()) -> nil()
0.07/0.19	 remove(x,.(y,z)) -> if(=(x,y),remove(x,z),.(y,remove(x,z)))
0.07/0.19	
0.07/0.19	Proof:
0.07/0.19	 Open
0.07/0.19	EOF