C++ challenge from quizes

Question

What is the output and how did you get it ?

class A{
  public:
    A(){ foo();}
    ~A(){foo();}
  void foo(){
  cout<<3;
}
  void bar(){ foo();}
};

class B:public A{
  void foo(){cout<<2;}
};
int main(){
B b;
b.bar();
}

Answer 1

We have class A, and class B which is derived from class A.

B b;

Object b of class B is created and the constructors are called. Since class B has no explicitly defined constructor, the program calls class A constructor, which calls foo() from class A. Prints 3.

b.bar();

Method bar() called using object b. No method in class B goes by the name bar, so class A bar() method is called. bar() method calls foo(), and this foo() is from class A ( because bar() is from class A, and cannot access class B foo() ). Prints 3.

Program ends, destructors are called. Class A destructor calls foo() from class A again. Prints 3.

Output: 333

Answer 2

Those challenges are getting clearer for me thank you again <3