The benefit of using the const keyword is that the compiler might be able to make
optimizations based on the knowledge that the value of the variable will not change.
In addition, the compiler will try to ensure that the values won’t be changed
Of course, the same benefits apply to #defined constants. The reason to use const
rather than #define to define a constant is that a const variable can be of any
type (such as a struct, which can’t be represented by a #defined constant). Also,
because a const variable is a real variable, it has an address that can be used,
if needed, and it resides in only one place in memory