C++ Programming - MCQ Practice Questions

In C++, the default access specifier for class members is 'private'. Only for structs, the default is 'public'.

In C++, the colon (:) operator is used to specify inheritance. Syntax: class Derived : public Base {}

Virtual functions enable runtime polymorphism by allowing derived classes to override base class methods. The correct method is called based on the object type at runtime.

The 'protected' access specifier allows access from within the class and derived classes, but not from outside the class hierarchy.

The 'this' pointer is an implicit pointer that points to the current object. It's used to access member variables and functions of the current object.

Accessing private members from outside the class results in a compilation error. The compiler enforces access control at compile time.

The 'final' keyword (introduced in C++11) prevents a class from being used as a base class for further inheritance.

Polymorphism allows objects to take on multiple forms through compile-time (overloading) and runtime (overriding) mechanisms, enabling flexible and extensible code design.

A pure virtual function in C++ is declared with the 'virtual' keyword followed by '= 0'. This makes the function purely virtual, requiring derived classes to implement it.

The 'protected' access specifier allows derived classes to access members of the base class while keeping them hidden from the outside world.

In C++, an interface-like behavior is achieved using an abstract class containing only pure virtual functions. Derived classes must implement these functions, enforcing a contract.

Encapsulation is the bundling of data (attributes) and methods (functions) into a single unit called a class, hiding internal details from the outside world.

In C++, the default access specifier for class members is private, meaning they are not accessible outside the class by default.

A pure virtual function is declared with '= 0' and has no implementation in the base class. Derived classes must override it to create a concrete class.

An abstract class must contain at least one pure virtual function, making it impossible to instantiate objects of that class directly.

'this' is a constant pointer that points to the current object instance, allowing members to reference themselves.

Abstraction is the process of hiding complex implementation details and exposing only the necessary interface to users.

Multiple inheritance in C++ uses the syntax 'class Derived : public Base1, public Base2 { };' with appropriate access specifiers.

Private members are accessible only within the same class. Public members are accessible from anywhere, and protected members are accessible in derived classes.

The base class constructor is always called before the derived class constructor to ensure proper initialization of inherited members.