MAYBE
235.82/60.09	MAYBE
235.82/60.09	
235.82/60.09	Problem:
235.82/60.09	 active(f(X)) -> mark(if(X,c(),f(true())))
235.82/60.09	 active(if(true(),X,Y)) -> mark(X)
235.82/60.09	 active(if(false(),X,Y)) -> mark(Y)
235.82/60.09	 active(f(X)) -> f(active(X))
235.82/60.09	 active(if(X1,X2,X3)) -> if(active(X1),X2,X3)
235.82/60.09	 active(if(X1,X2,X3)) -> if(X1,active(X2),X3)
235.82/60.09	 f(mark(X)) -> mark(f(X))
235.82/60.09	 if(mark(X1),X2,X3) -> mark(if(X1,X2,X3))
235.82/60.09	 if(X1,mark(X2),X3) -> mark(if(X1,X2,X3))
235.82/60.09	 proper(f(X)) -> f(proper(X))
235.82/60.09	 proper(if(X1,X2,X3)) -> if(proper(X1),proper(X2),proper(X3))
235.82/60.09	 proper(c()) -> ok(c())
235.82/60.09	 proper(true()) -> ok(true())
235.82/60.09	 proper(false()) -> ok(false())
235.82/60.09	 f(ok(X)) -> ok(f(X))
235.82/60.09	 if(ok(X1),ok(X2),ok(X3)) -> ok(if(X1,X2,X3))
235.82/60.09	 top(mark(X)) -> top(proper(X))
235.82/60.09	 top(ok(X)) -> top(active(X))
235.82/60.09	
235.82/60.09	Proof:
235.82/60.09	 Open
235.82/60.09	EOF