Technical interview questions and answers play a major role in C++ Interviews because C++ is widely used in system programming, game development, competitive coding, and performance-critical applications. Companies expect candidates to know OOP concepts, classes, inheritance, polymorphism, references, memory management, STL, and exception handling. These questions often appear in campus placements and software interviews conducted by TCS, Wipro, Infosys, Cognizant, and Capgemini. This guide covers frequently asked C++ interview questions with simple explanations that help freshers and job seekers strengthen their programming foundation. Preparing these questions will help you perform well in coding tests, technical rounds, and real-time problem-solving interviews.
Showing 10 of 92 questions
71. What is destructor?
Destructor is a special member function of a class, which is invoked automatically whenever an object goes out of the scope. It has the same name as its class with a tilde character prefixed.
72. What is an explicit constructor?
A conversion constructor declared with the explicit keyword. The compiler does not use an explicit constructor to implement an implied conversion of types. Its purpose is reserved explicitly for construction.
73. What is the Standard Template Library?
A library of container templates approved by the ANSI committee for inclusion in the standard C++ specification. A programmer who then launches into a discussion of the generic programming model, iterators, allocators, algorithms, and such, has a higher than average understanding of the new technology that STL brings to C++ programming.
74. What problem does the namespace feature solve?
Multiple providers of libraries might use common global identifiers causing a name collision when an application tries to link with two or more such libraries. The namespace feature surrounds a librarys external declarations with a unique namespace that eliminates the potential for those collisions. This solution assumes that two library vendors dont use the same namespace identifier, of course.
75. What is the use of ‘using declaration?
A using declaration makes it possible to use a name from a namespace
76. What is a template?
Templates allow us to create generic functions that admit any data type as parameters and return a value without having to overload the function with all the possible data types. Until certain point they fulfill the functionality of a macro. Its prototype is any of the two following ones:
template function_declaration;
template function_declaration;
77. Differentiate between a template class and class template?
Template class:
A generic definition or a parameterized class not instantiated until the client provides the needed information. Its jargon for plain templates.
Class template:
A class template specifies how individual classes can be constructed much like the way a class specifies how individual objects can be constructed. Its jargon for plain classes.
78. What is the difference between a copy constructor and an overloaded assignment operator?
A copy constructor constructs a new object by using the content of the argument object. An overloaded assignment operator assigns the contents of an existing object to another existing object of the same class.
79. What is a virtual destructor?
The simple answer is that a virtual destructor is one that is declared with the virtual attribute.
80. What do you mean by Stack unwinding?
It is a process during exception handling when the destructor is called for all local objects between the place where the exception was thrown and where it is caught.