//
// What is it about ?  
//
 
#include <iostream>
#include <string>
#include <memory>
#include <vector>
 
using namespace std; 
struct A {
	A() : i(std::make_shared<std::vector<std::shared_ptr<int>>>()) {}
 
	A(const A &other) {
		i = other.i;
	}
 
	std::shared_ptr<std::vector<std::shared_ptr<int>>> i;
};
 
struct B : public A {
	B(const A &other) : A(other) {}
};
 
int main(int ac, char**av) 
{
	cout << "...\n"; 
 
	{ // throw
		A a;
		B b(a);
 
		b.i->emplace_back(std::make_shared<int>(10));
		printf("%d\n", *a.i->at(0));
	}
 
 
	//cin.ignore(SIZE_MAX, '\n');
	cout << "Press Enter";
	cin.get(); 
	return 0;
}

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