C++ Programming - References - Discussion

2 is correct
becuase a refrence can be thaught of as (*p) where we can not change p is true but a is value at that pointer
so a reference is a value_at-cannot_be_changed_by_us-pointer
and is not a constant pointer

You can always change the address being pointed by 'p' and also value at 'p' unless they are constant similar is the case with the reference variable.

Can anyone please explain. Why the 2nd option is incorrect?

2 is incorrect because reference once created alias i.e., initialized with the variable must not be assigned once again with the another new another. So, it seems like const pointer.

Pointer can change its reference, it is not a constant.

What does the second statement mean?

A reference is not a constant pointer.

Pointer take the reference of another variable also and it is not a constant pointer because we can change it.

- Pointer has its own address. Reference (const or not) does not.

- Const pointer can be NULL. Reference can not.

- You can test for NULL pointer being returned by a function. You cannot test for NULL-reference, even if object being referenced went out of scope.

- You need to deference the pointer to access it's data, there is no deference a reference.

All that makes references conceptually and practically different from const pointers, even though under the hood they can be implemented as the same mechanism by a compiler.

"The C++ standard does not force compilers to implement references using.

"The C++ standard does not force compilers to implement references using pointer.

The Answer mentioned is wrong.

A reference variable can't refer to any other variable once it has been defined to refer to a particular variable.

The correct answer should be option [B].