Explain C++ virtual dispatch and object lifetime

Answer the following C++ fundamentals questions. ## 1) Virtual function dispatch: predict output Consider this C++ program: ```cpp #include <iostream> using namespace std; struct Base { Base() { cout << "Base()\n"; } virtual void vf() { cout << "Base::vf\n"; } void nvf() { cout << "Base::nvf\n"; } virtual ~Base() { cout << "~Base()\n"; } }; struct Derived : Base { Derived() { cout << "Derived()\n"; } void vf() override { cout << "Derived::vf\n"; } void nvf() { cout << "Derived::nvf\n"; } ~Derived() override { cout << "~Derived()\n"; } }; int main() { Base* p = new Derived(); p->vf(); p->nvf(); delete p; } ``` - What is the exact output (line by line)? - Explain why each line prints (virtual dispatch vs non-virtual binding, and destructor behavior). ## 2) Destructors and dangling pointers For each snippet below: - identify whether it is correct, leaks memory, causes undefined behavior, or creates a dangling pointer; - explain why; - show a safer/fixed version. ### (a) ```cpp int* make() { int x = 42; return &x; } ``` ### (b) ```cpp int* p = new int(7); delete p; cout << *p << "\n"; ``` ### (c) ```cpp int* p = new int(7); int* q = p; delete p; delete q; ``` ## 3) Pointer vs reference Explain the differences between pointers and references in C++ (at least: nullability, reseating, ownership semantics, parameter passing, const behavior), and give examples of when you would choose each.