This is one of those questions that sounds contained but keeps expanding.
Start by defining smart pointers as RAII wrappers that automate memory management, then contrast their ownership semantics with raw pointers. Walk through unique_ptr, shared_ptr, and weak_ptr, explaining their tradeoffs and how they prevent leaks but can introduce reference cycles. Conclude with practical guidelines for choosing the right pointer type.
Pro tip: Mention that shared_ptr's control block overhead and atomic reference counting can be a performance bottleneck in multithreaded code, and that weak_ptr is essential for breaking cycles in observer patterns or caches.
Explain that smart pointers are objects that own and manage a raw pointer, automatically deallocating when out of scope via RAII. Contrast with raw pointers, which have no ownership semantics and require manual delete.
Describe how smart pointers encode ownership: unique_ptr for exclusive ownership, shared_ptr for shared ownership via reference counting, and weak_ptr for non-owning references. Highlight that lifetimes are tied to scope and reference counts, preventing leaks and dangling pointers.
Detail unique_ptr (zero overhead, move-only), shared_ptr (thread-safe ref counting, overhead), and weak_ptr (breaks cycles, no ownership). Mention custom deleters and make_* factory functions.
Cover reference cycles with shared_ptr and how weak_ptr solves them. Warn against mixing raw and smart pointers, and note that shared_ptr is not a silver bullet for all sharing scenarios.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.