What should not be in a constructor?

Don’t use init()/cleanup() members . If you have to call init() every time you create an instance, everything in init() should be in the constructor. The constructor is meant to put the instance into a consistent state which allows any public member to be called with a well-defined behavior.

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What is class object in programming?

In object-oriented programming, a class is a blueprint for creating objects (a particular data structure) , providing initial values for state (member variables or attributes), and implementations of behavior (member functions or methods). The class is a blueprint that defines a nature of a future object. …

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