C++ Core Concepts

Question 1

Encapsulation

Answer 1

Bundling data and methods; controlling access to internal state.

Question 2

Inheritance

Answer 2

Deriving a class from another to reuse/extend functionality.

Question 3

Polymorphism

Answer 3

Ability for objects to take many forms; typically via virtual functions.

Question 4

Abstraction

Answer 4

Hiding implementation details behind a defined interface.

Question 5

Composition

Answer 5

Building classes by including instances of other classes rather than inheriting.

Question 6

RAII
(Resource Acquisition Is Initialization)

Answer 6

resource lifetime is tied to object lifetime for deterministic cleanup

Question 7

PIMPL
(Pointer to Implementation)

Answer 7

Hiding implementation details to reduce compile-time dependencies.

Question 8

unique_ptr

Answer 8

exclusive ownership of a resource

Question 9

shared_ptr

Answer 9

reference-counted shared ownership

Question 10

weak_ptr

Answer 10

non-owning reference to a shared pointer

Question 11

Value Semantics

Answer 11

Object copies own their data independently.

Question 12

Reference Semantics

Answer 12

Objects refer to shared data rather than copying.

Question 13

Copy Semantics

Answer 13

Creates a new object as a duplicate of an existing object

Question 14

Move Semantics

Answer 14

Transfers ownership of resources from one object to another without duplicating them

Question 15

Deep Copy

Answer 15

Copying all object data recursively.

Question 16

Shallow Copy

Answer 16

Copying only references/pointers, not owned data.

Question 17

Constructor

Answer 17

function of a class that is automatically called when an object is created

Question 18

Destructor

Answer 18

function called automatically when an object goes out of scope or is deleted

Question 19

Overloading

Answer 19

Defining multiple functions/operators with the same name but different parameters.

Question 20

Explicit

Answer 20

Forces the conversion of one type to another to be done manually

Question 21

Implicit

Answer 21

compiler automatically converts one type to another when needed

Question 22

Immutable

Answer 22

Data that cannot be changed after creation

Question 23

Mutable

Answer 23

Data marked as this can be modified even inside const member functions

Question 24

Lambdas

Answer 24

Inline anonymous functions with optional captures.

Question 25

Templates

Answer 25

Generic programming for type-agnostic code.

Question 26

Constexpr

Answer 26

Compile-time constants and functions.

Question 27

Scope

Answer 27

Lifetime and visibility of variables.

Question 28

Namespace

Answer 28

Organizing symbols to avoid name collisions.

Question 29

Public access

Answer 29

Members are accessible anywhere the object is visible

Question 30

Private access

Answer 30

Members are accessible only inside the class (and friends)

Question 31

Protected access

Answer 31

Members are accessible in the class and its derived classes

Question 32

Static

Answer 32

makes one value or function exist once and be reused, rather than recreated each time

Question 33

lvalue

Answer 33

expression with an identifiable memory location and persistent lifetime

Question 34

rvalue

Answer 34

temporary value without a stable memory location, often eligible for moving

Question 35

invariant

Answer 35

property/state that must remain true for the lifetime of an object.