C++ for placements: interview questions by topic

C++ topics, one page each

8 of the 8 C++ topics in the bank have a page so far; the diagnostic draws from all 8.

1. C++ references and const interview questions

   C++ references and const as interviews test them: references versus pointers, passing by const reference, dangling references, constexpr.

2. C++ classes and constructors interview questions

   C++ classes as interviews test them: the rules of three, five and zero, = default and = delete, explicit, delegating constructors, copy elision.

3. C++ inheritance interview questions

   C++ inheritance beyond virtual: base constructors with arguments, name hiding and using, static_cast versus dynamic_cast, typeid, virtual clone.

4. C++ operator overloading interview questions

   C++ overloading as interviews test it: member versus free operators, printing with <<, copy-and-swap, function objects, const overloads and <=>.

5. C++ smart pointers and memory interview questions

   C++ memory as interviews test it: new and delete[], RAII, unique_ptr, shared_ptr and weak_ptr, make_unique and make_shared, custom deleters.

6. C++ templates interview questions

   C++ templates as interviews test them: instantiation versus Java generics, headers, specialisation, non-type parameters, variadic templates, concepts.

7. C++ STL interview questions

   The C++ STL as interviews test it: choosing a container, vector capacity, iterator invalidation, map versus unordered_map, emplace and custom sorts.

8. C++ lambdas and move semantics interview questions

   Modern C++ as interviews test it: lambda captures and mutable, lvalues and rvalues, std::move, move constructors, perfect forwarding and noexcept.

One question, exactly as the diagnostic asks it

From the C++ bank — 30 questions across 8 topics. The answer is marked because this one is public; in a sitting you choose first, then see why each option is right or wrong.

auto a = std::make_shared<int>(1);
auto b = a;
{
    auto c = a;
    std::cout << a.use_count();
}
std::cout << a.use_count();