C++ Interview Questions and Answers

What is C++?

C++ is an object-oriented programming language created by Bjarne Stroustrup in 1985.

What are the differences between C and C++?

C++ is a superset of C language.

C is a procedural programming language, but C++ supports both procedural and Object Oriented programming.

In C++ can use access modifier to restrict access of member function and variable to outside class and user, but in C we can’t do that.

What are the differences between C++ and Java?

C++ has pointers, but Java does not support pointer.
Java is platform-independent, but C++ is not.
Java has garbage collection, but C++ does not.
C++ used complier but Java uses interpreter.
C++ support operator overloading and multiple inheritance but Java not support both.

Explain is Object Oriented Programming (OOP)?

Object-oriented programming is a techniques for managing enormous complexity, achieving reuse of software components, and coupling data with the procedures that work on that data as a single "object"--a self-contained entity.

The basic concepts of Object Oriented Programming are given below:
Class and Object: Class is a template and implementation of entities whereas Object is variable and representation of class.
Encapsulation and data hiding: the binding of data and methods together called Encapsulation, where hide the data or direct access from outside known as data hiding.
Inheritance: Inheritance is concept of reusability and can used this to inherit the property of one class into another class.
Polymorphism: Poly means many, and morph means form. Polymorphism refers to the same name taking many forms or can perform different task depend on context.

What is a class in C++?

Class is a user-defined data type. It can consist of any combination of the variable types and also other class types.
The variables in the class are referred to as the member variables or data members and the functions in the class referred to as member Functions or methods of the class.

What is an object?

An object is an individual instance of a class and also called a class variable.
It can access the class members and functions by using the dot (.) operator.

Define the private, public and protected in C++?

Private, Public and protected and are three access specifier in C++.

Private: All members of a class data and methods are private by default. Private members can be accessed only within methods of the class itself.
Public: Public members can be accessed through any object of the class.
Protected: data members and member functions are only available to derived classes.

Explain constructor?

Constructors is special member function of class with the same name as the class and it used to create and initialize Object.
The constructor can take parameters as needed, but it cannot have a return value--not even void.
We can do Overloading of Constructor.

Explain destructor?

Destructors always has the name of the class, preceded by a tilde (~) and clean up allocated memory. Destructors take no arguments and have no return value.
We cannot Overload of destructor.

What is Default Constructors and Destructors?

If we don't declare a constructor or a destructor manually, the compiler makes one for you. The default constructor and destructor take no arguments and do nothing.

What is a copy constructor?

A copy constructor is the constructor which copies the exact values of one object's member variables into another object.
Copy constructors take one parameter, which a reference to an object of the same class.

Explain the static variable and member function?

Static variables and member functions belonging to the class rather than to the object. Normal member data is one per object, but static members are one per class and they can be called without having an object of that class.

 

Latest Updates

Trigonometry

What is the value of cot 4π/3 ?

Indian Politics

Article-24 of the Indian Constitution ‘Prohibition of employment of children in factories, etc’ deals with?

Article-134A of the Indian Constitution ‘Certificate for appeal to the Supreme Court’ deals with?

Chemistry

Who invented Aspirin?

Physics

A larger force on a rotating body results in larger?

What is the unit of the physical quantity, magnetic flux density?

Algebra

The system of equations 2x + 4y = 6 and 4x + 8y = 8 is ?

Time and Distance

A thief is spotted by a policeman from a distacne of 100 m. When the policeman starts the chase, the thief also starts running. If the speed of the theif is 8 km / hour and that of the policeman is 10 km/hour, then how far will the theif have to run before he is overtaken?

Algebra

Aman and Alok attempted to solve a quadratic equation. Aman made a mistake in writing down the constant term and ended up in roots (4, 3). Alok made a mistake in writing down the coefficient of x to get roots (3, 2). The correct roots of the equation are?

Compound Interest

The effective annual rate of interest corresponding to a nominal rate of 22% per annum payable half-yearly is?

Volume and Surface Area

If the volume of a cylinder is 2156 cubic cm and height is 14 cm, find its radius?

Algebra

What is the equation of the line which passes through the points (2, 3) and (- 4, 1)?

Triangles

In △ABC, the angle bisector of ∠A cuts BC at E. Find length of AC, if lengths of AB, BE and EC are 9 cm, 3.6 cm and 2.4 cm?

In a triangle, the length of the opposite side of the angle which measures 45° is 8√2 cm, what is the length of the side opposite to the angle which measures 90°?

General Knowledge of India

The boundary line between India and Pakistan is called?

Which city is located on the banks of the river Mahanadi?

Indian History

When was the battle of Haldighati fought?

In 1498, which Portuguese explorer discovered a new sea route from Europe to India?

General Knowledge of India

Chapchar Kut is a festival of which State?

Chemistry

In chemistry, soap is a salt of a ?

Indian Economy

Which of the following is a Direct tax?

Biology

Sauria lacertidae is the scientific name of?

Which of the following is a primary function of haemoglobin?

Average

A factory buys 8 machines.3 Machine A, 2 Machine B and rest Machine C. Prices of the machines are 100000, 80000 and 45000 respectively.Calculate the average cost of these machines?

Discount

Ticket for an adult is 500 and a child is 200. 1 child goes free with two adults. If a group has 20 adults and 8 children what will be the discount the group get?