How destructors help to release memory?

Question

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Answer 1

The memory used to store old objects can be freed up to create new objects. As memory is a finite resource, releasing memory is important in software that can consume a lot of it.

Answer 2

If you dynamically allocate memory in a class(with new), you should free that memory (with delete) to prevent memory leaks. Usually, the class destructor is a good place to do that.