在八枚外观相同的硬币中，有一枚是假币，并且已知假币与真币的重量不同，但不知道假币与真币相比较轻还是较重。可以通过一架天平来任意比较两组硬币，设计一个高效的算法来检测出这枚假币-In the eight coins look the same, there is a counterfeit money and counterfeit currency and real currency known to the weight of different, but do not know the real currency of counterfeit money when compared with lighter or heavier. Through a balance to compare any two coins, design an efficient algorithm to detect counterfeit money 这枚