#include <iostream>
#include <vector>
#include <memory>
using namespace std;
 
class Shape {
public:
	virtual void draw() { cout<<"Not implemented yet, but making it abstract wouldn't compile"<<endl;}
	virtual ~Shape() {}; 
};
class Rectangle : public Shape {
public:
	void draw() override { cout<<"Rectangle"<<endl;}
};
class Circle : public Shape {
public:
	void draw() override { cout<<"Circle"<<endl;}
};
 
int main() {
	cout << "Demo of slicing:"<<endl;
	vector<Shape> vs;   // no pointers, slicing
	vs.emplace_back(Rectangle()); 
	vs.emplace_back(Circle());	
	vs.emplace_back(Rectangle()); 
	for (auto& x:vs) x.draw(); 
 
	cout << endl<<"Demo of polymorphism:"<<endl;
	vector<shared_ptr<Shape>> vp;   // polymorhpic container
	vp.emplace_back(make_shared<Rectangle>()); 
	vp.emplace_back(make_shared<Circle>());	
	vp.emplace_back(make_shared<Rectangle>()); 
	for (auto& x:vp) x->draw(); 
	// no worry about leaking: shared_ptr will destroy objects when no longer needed
 
	return 0;
}

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