C++ is a powerful and widely used programming language that has many applications in various industries and domains in India. It is a high-performance language that is used for developing operating systems, games, desktop applications, embedded systems, and more. We will discuss Top C++ Interview Questions and Answers for 2023 in this article.
In India, C++ is an important language for software development and is widely used in the IT industry. Many top IT companies in India, like TCS, Infosys, Wipro, and HCL, use C++ extensively in their software development projects. Additionally, C++ is also widely used in the automotive industry for developing software for car systems. It is also used in the finance industry for developing trading and risk management systems.
Top C++ Interview Questions and Answers for 2023
Here are some top C++ interview questions and answers that you may encounter during a job interview in 2023:
1. What is C++?
Answer: C++ is a high-level, object-oriented programming language that is used to develop software applications. It was developed by Bjarne Stroustrup in 1983 as an extension of the C language.
2. What are the advantages of using C++ over other programming languages?
Answer: Some advantages of using C++ include its high performance, ability to provide low-level memory access, and its support for object-oriented programming.
3. What is an object in C++?
Answer: An object in C++ is an instance of a class that encapsulates data and functions. It can be used to represent a real-world entity or a software component.
4. What is polymorphism in C++?
Answer: Polymorphism is a feature of object-oriented programming. It allows objects of different classes to be treated as if they are of the same type. It can be achieved through function overloading, operator overloading, and virtual functions.
5. What is the difference between pass by value and pass by reference in C++?
Answer: In pass by value, a copy of the argument is passed to the function. In pass by reference, a reference to the argument is passed. Pass by reference allows the function to modify the original argument, whereas pass by value does not.
6. What is a constructor in C++?
Answer: A constructor is a special member function that is called when an object of a class is created. It is used to initialize the data members of the object.
7. What is a destructor in C++?
Answer: A destructor is a special member function that is called when an object of a class is destroyed. It is used to free any resources that were allocated by the object.
8. What is a template in C++?
Answer: A template is a generic class or function that can be used with different data types. It allows the same code to be reused with different types of data.
9. What is a namespace in C++?
Answer: A namespace is a mechanism in C++ that allows you to group related classes, functions, and variables under a single name. It is used to avoid naming conflicts and to organize code.
10. What is the difference between a class and a structure in C++?
Answer: In C++, a class is a user-defined data type that encapsulates data and functions. A structure is a user-defined data type that only encapsulates data. However, in practice, the only difference between a class and a structure is the default access modifier. Public for struct and private for class.
11. What is the difference between an array and a vector in C++?
Answer: An array is a fixed-size data structure that stores a collection of elements of the same data type. A vector is a dynamic data structure that can grow or shrink in size and stores elements of the same data type.
12. What is the difference between a pointer and a reference in C++?
Answer: A pointer is a variable that stores the memory address of another variable. A reference is an alias for another variable. Once a reference is initialized, it cannot be changed to refer to a different variable.
13. What is operator overloading in C++?
Answer: Operator overloading is a feature of C++ that allows operators to be used with user-defined data types. It allows you to define the behavior of operators like +, -, *, /, and == for objects of a class.
14. What is virtual inheritance in C++?
Answer: Virtual inheritance is a feature of C++. It allows a class to inherit from a base class such that if there are multiple paths to the base class through the inheritance hierarchy. The base class is only instantiated once.
15. What is a friend function in C++?
Answer: A friend function is a non-member function that is granted access to the private members of a class. It is declared in the class definition with the keyword friend.
16. What is multiple inheritance in C++?
Answer: Multiple inheritance is a feature of C++ that allows a class to inherit from multiple base classes. It can lead to complications such as name conflicts and the diamond problem.
17. What is the difference between public, private, and protected access specifiers in C++?
Answer: Public members can be accessed from anywhere, private members can only be accessed from within the class, and protected members can be accessed from within the class and its derived classes.
18. What is a template specialization in C++?
Answer: Template specialization is a feature of C++ that allows a template to have a different implementation for a specific data type or set of data types.
19.What is the difference between a copy constructor and an assignment operator in C++?
Answer: A copy constructor creates a new object that is a copy of an existing object. An assignment operator assigns the value of an existing object to another existing object.
20. What is the difference between a shallow copy and a deep copy in C++?
Answer: A shallow copy copies only the memory address of an object. A deep copy copies the contents of the object.
C++ is a powerful and widely used programming language. It is important for candidates to be well-prepared for C++ job interviews. These top 20 C++ interview questions and answers cover a range of topics including pointers, inheritance, memory management, and more. By studying these questions and practicing your coding skills, you can increase your chances of success in C++ job interviews and kickstart your career as a C++ developer.
Top C++ Interview Questions and Answers for 2023: FAQs?
1. What are the key skills required for a C++ developer?
Ans. A C++ developer should have strong programming skills. He/she must have knowledge of object-oriented programming concepts. The developer must be familiar with data structures and algorithms. He/she should have a good understanding of memory management. Finally , he/she should be proficient in debugging and troubleshooting.
2. What are the common C++ interview questions?
Ans. Some common C++ interview questions include questions on :
- Memory management
- Inheritance, polymorphism
- Operator overloading
- Virtual functions
- Exception handling, and
- Standard libraries.
3. How can I prepare for a C++ interview?
Ans. To prepare for a C++ interview, you should review C++ fundamentals, practice coding exercises, study commonly asked interview questions. Last but not the least, familiarize yourself with the company and its products/services.
4. What is the difference between C and C++?
Ans. C is a procedural programming language, whereas C++ is an object-oriented programming language that includes features of C. C++ supports classes, inheritance, polymorphism, templates, and other advanced features that are not available in C.
5. What is the importance of C++ in the software industry?
Ans. C++ is widely used in the software industry for developing operating systems, compilers, games, databases, and other applications that require efficient and high-performance code. C++ is also used in embedded systems, finance, healthcare, and other domains that require robust and reliable software solutions.
6. What is the salary range for a C++ developer?
Ans. The salary range for a C++ developer varies depending on location, experience, and company size. According to Payscale, the average salary for a C++ developer in the United States is around $85,000 per year.