Some Concepts

const char * and char * const
- the first is a pointer to a constant char while the second is a const pointer to a char
- so for the first, you can not change the value but you can change the pointer, for the second, you cannot change the pointer but you can change the value
- and note const char * and char const * are the same, so you cannot change the value but you can change the pointer
Static member in a class :
- We can define class members static using static keyword. When we declare a member of a class as static it means no matter how many objects of the class are created, there is only one copy of the static member.
- Static variables in the context of a class are shared between all instances of a class.
  
  In a function, it remains a persistent variable, so you could for instance count the number of times a function has been called.
  
  When used outside of a function or class, it ensures the variable can only be used by code in that specific file, and nowhere else.
  
  Constant variables however are prevented from changing. A common use of const and static together is within a class definition to provide some sort of constant.
- so whenever you want to declare some constant values in a class as a member, use static!!!!
  eg: static const a = 1;

CPP Notes