Reference vs pointer in C++ - Quick Revision & Key Differences

Recall & Review

beginner

What is a reference in C++?

A reference is an alias for another variable. It must be initialized when declared and cannot be changed to refer to another variable later.

beginner

What is a pointer in C++?

A pointer is a variable that stores the memory address of another variable. It can be reassigned to point to different variables.

intermediate

Can a reference be null in C++?

No, a reference must always refer to a valid object. It cannot be null.

intermediate

Can a pointer be null in C++?

Yes, a pointer can hold a null value, meaning it points to no object.

beginner

How do you access the value pointed to by a pointer?

You use the dereference operator (*) to access or modify the value the pointer points to.

Which of the following must be initialized when declared?

A Reference

B Pointer

C Both reference and pointer

D Neither

References must be initialized when declared; pointers can be declared without initialization.

Can a pointer be reassigned to point to a different variable?

A No, pointers are fixed

B Yes, pointers can be reassigned

C Only if the pointer is const

D Only references can be reassigned

Pointers can be reassigned to point to different variables anytime.

Which can be null in C++?

A Pointer

B Neither

C Both

D Reference

Pointers can be null; references cannot.

How do you access the value a pointer points to?

A Using the & operator

B Using the -> operator

C Using the * operator

D Using the . operator

The * operator dereferences the pointer to access the value.

Which statement about references is true?

A References can be reseated to another variable

B References store memory addresses

C References can be null

D References are aliases and cannot be changed after initialization

References act as aliases and cannot be changed to refer to another variable after initialization.

Explain the main differences between a reference and a pointer in C++.

Think about initialization, nullability, and how you use them.

Describe a situation where you would prefer to use a pointer over a reference.

Consider flexibility and nullability.