#include <memory>
#include <stdio.h>

class C2{
	public:
	int data=4;
	~C2(){
		printf("C2 destroyed\n");
	}
};

class C1{
	public:
	~C1(){
		printf("C1 destroyed\n");
	}
	void PrintData(std::weak_ptr<C2>ptr) {
		printf("Data is %d\n",ptr.lock()->data);
	}
};


int main(){
  	
	std::shared_ptr<C1> ptrA{std::make_shared<C1>()};

	std::weak_ptr<C1>ptrA_2=ptrA;
	if (!ptrA_2.expired()) {
		printf("Count:%ld",ptrA.use_count());
		std::shared_ptr<C1> ptrA_3{ptrA};
		printf("Inside if statement.\n");
		std::shared_ptr<C2> ptrB{std::make_shared<C2>()};
		ptrA_2.lock()->PrintData(ptrB);
		printf("Count:%ld",ptrA.use_count());
	}
		printf("Count:%ld",ptrA.use_count());
	printf("Outside if statement.\n");
	
	return -1;
}