火烧尾的专栏

适配器模式：将一个类的接口转换为客户

class product { public: virtual void show() = 0; } class productA: public product { public: void show(){ cout << "productA" << std::endl;} } class productB : public product { public: voi

class FactoryA : Factory { }

策略模式可以根据用户需要更新

代码：class Singleton(object): _inst = None def new(cls): if cls._inst is None: inst = object.new(cls)