Question

How can we write a function which swap enum variables?

Also are these variables standard and working with them doesn’t matter in a project?
How do C++ complier use them and put them in the RAM?

Answer 1

Use std::swap:

enum Foo {
    CAT,
    DOG,
    ELEPHANT
};

Foo a = CAT;
Foo b = ELEPHANT;

std::swap(a, b);

std::cout << (a == ELEPHANT) << "\n";

enum is perfectly standard; they are equivalent to integer types.