#include <bits/stdc++.h>
using namespace std;

class A {
public:
    A() {
        cout << "Class A Object created" << endl;
    }
};


class B {
private:
    A a;
public:
    B(A arg): a(arg) {
        cout << "Class B Object created" << endl;
    }
};

class C {
private:
    A a;
public:
    C(A& arg): a(arg) {
        cout << "Class C Object created" << endl;
    }
};

class D {
private:
    A& a;
public:
    D(A& arg): a(arg) {
        cout << "Class D object created" << endl;
    }
};

void test() {
    A a;
    cout << "----------" <<  endl;
    B b(a);
    cout << "----------" <<  endl;
    C c(a);
    cout << "----------" <<  endl;
    D d(a);
    cout << "----------" <<  endl;
}

int main() {
    test();
    return 0;
}