Understanding a weak reference counter

Question

When creating shared_ptr, the manager object uses strong and weak reference counters. I understand that using a strong reference counter, shared_ptr knows when to free a managed entity, but I don’t understand why it uses a weak reference counter.

Answer 1

There are two objects associated with shared_ptr<T>and weak_ptr<T>:

• actual object ( T)
• control unit containing common and weak counters

, 0. , , .. , 0.

Answer 2

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Answer 3

weak_ptr , , , . , - , , .