Implement unique_ptr

Implementing a custom unique_ptr with ownership tracking

This is an easy C++ coding problem that tests your understanding of move semantics, resource ownership, and smart-pointer design patterns. It's the kind of foundational question quant firms ask to verify you can implement low-level abstractions correctly—essential for building robust trading systems and risk engines.

The problem requires you to build a single-ownership smart pointer from scratch, implementing the full suite of constructors and assignment operators, then adding custom utility methods. The key challenges are ensuring move semantics transfer ownership safely, deliberately throwing on copy attempts, and managing cleanup through a custom deleter. You'll also need to track ownership state and expose it via a utility method.

• Move semantics (constructor and assignment) and safe "moved-from" state
• Exception-throwing copy operations and their role in ownership models
• RAII: resource acquisition and cleanup via constructor/destructor
• Operator overloading (dereference, arrow, bool conversion)
• Custom deleters and their invocation semantics