I do not think you have discribed the question properly. And "两个开关,一个只能把灯打开,另一个只能把灯关上" is mission impossible. :-) I wanna know who asked you to do this? What's the context?
expertune(专家 GUID)
(#333187@0) Last Updated: 2002-1-13 This post has been archived. It cannot be replied.