class classA
{
	public:
		
		virtual void test() = 0;
};

class classB : public classA
{
	public:
		
		void test()
		{
			cout << "blah";
		}
};

void tester(classA* object)
{
	object->test();
};


int main()
{	
	classB* blah = new classB;
	tester(blah);
	
	return 0;
}