#include <iostream>
#include <memory>
using namespace std;

class A {
public:
    unique_ptr<int> data;

    A(int *d) : data(d) {
        throw runtime_error("error");
    }
};

class B {
public:
    unique_ptr<int[]> data2;
    unique_ptr<A> a;

    B() : data2(new int[10]),
          a(new A(new int(5))) {
    }

    //~B() = default;

};


int main() {
    try {
        B b;
    }
    catch (exception) {

    }

}