#include <iostream>

using std::cout;

struct A {
  A() = default;
  A(int x) { val = x; }
  void print() { cout << "A(" << val << ")"; }
  int val;
};

struct B {
  // B(int x) { a = A(x); }
  B(int x) : a(x) {}
  void print() {
    cout << "B(";
    a.print();
    cout << ")";
  }
  A a;
};

int main() {
  B b(10);
  b.print();
  cout << "\n";
}