Static

Question

What is the different between static and -“non-static”? Why do we need that not making instance thing and where is better to use the other one?

Answer 1

A static member of a class belongs to the class and not to the instance of a class. For example, a counter to count how many objects which has been instantiated. We clearly don't want the counter to be re-instantiated to 0 with every new object. We also don't want every object to have it's own counter - We want the class to have a counter, so we declare it as static. It looks something like:

class A {
static int counter = 0;
A () { counter++; }
};

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