using namespace std;

#include <iostream>
static int count;

class A{

public:
    int c;
    A(){c = ++count; cout << "A() " << c << endl;}
    A(int j){c = ++count; cout << "A(int) " << c << endl;}
    ~A(){cout << "~A() " << c << endl;}

};

class B{
    public:
        A a;
        B(){
        cout << "This is B's constructor" << endl;
        A a(); //This is the important line.
    }
};

int main(){
    B b;
    cout << "The object we keep is " << b.a.c << endl;
}

A() 1
This is B's constructor
The object we keep is 1
~A() 1

A() 1
This is B's constructor
A(int) 2
~A() 2
The object we keep is 2
~A() 2

A a(); //This is the important line.

A a{}; // *this* is a variable declaration