#include <iostream>
using namespace std;
class Parent{
	public:
		Parent(){};
		virtual~Parent(){
			cout << "destructor parent\n";
		}
		virtual void fn(){
			cout << "call parent fn\n";
		}
};
class Child:public Parent{
	public:
		~Child(){
			cout << "destructor child\n";
		}
		virtual void fn(){
			cout << "call child fn\n";
		}
};
void test(Parent &obj){
	obj.fn();
}
int main() {
	Parent obj1;
	Child obj2;
	Parent *obj3 = new Child;
	test(obj1);
	test(obj2);
	test(*obj3);
	delete obj3;
	return 0;
}

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