cpp_prac/junk/1.5.cc

#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";
}