Convert to PIMPL

Understanding the PIMPL idiom in C++

This easy coding problem tests your ability to refactor a class using the Pointer to Implementation (PIMPL) idiom, a common encapsulation technique in C++. PIMPL separates the public interface from implementation details by hiding the actual logic behind a pointer, allowing internal changes without recompiling client code that depends on the header.

The challenge requires you to restructure a given class so that all data members and complex logic move into a separate implementation class, with the public interface holding only a pointer to that implementation. This approach decouples the header file's binary layout from changes to the implementation, reduces compilation dependencies, and maintains a stable ABI across builds. You'll need to manage object lifetime correctly and ensure the refactored class supports move semantics efficiently.

• Pimpl pointer ownership and destruction
• Move constructors and move-assignment operators
• Separating interface from implementation
• Binary size and memory layout constraints