His address is the address of the variable that the pointer points to. It is wrong for the two upstairs to assign integer constants directly to pointer variables. Although the compiler only has warnings and no errors, it is meaningless. It's a very dangerous operation.

So is this address a constant? In general, after applying for memory space, the position of variables will not change.

The address will not change. However, it is not standard to say that he is a constant. Because with or without variables. Memory addresses always exist.