What are the differences between std::unique_ptr and std::shared_ptr in C++?

Can you explain the differences between std::unique_ptr and std::shared_ptr in C++?

Sure! std::unique_ptr is a smart pointer that owns a dynamically allocated object exclusively, meaning no two unique_ptrs can own the same object. In contrast, std::shared_ptr allows multiple pointers to share ownership of the same object, using reference counting to manage the object's lifetime.

When should I use std::unique_ptr instead of std::shared_ptr?

You should use std::unique_ptr when you want sole ownership of an object and don't need to share it. It's more efficient because it doesn't involve reference counting.

Are there any performance implications of using std::shared_ptr?

Yes, std::shared_ptr has some overhead due to reference counting. Each time a shared_ptr is copied or destroyed, it updates the reference count, which can be less efficient than using unique_ptr.

Can std::unique_ptr be converted to std::shared_ptr?

Yes, you can convert a std::unique_ptr to a std::shared_ptr by using std::move to transfer ownership, but this will create a new shared_ptr that takes over the unique_ptr's resource.