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Top 44 C++ Interview Questions & Answers (2026)

44 Questions 20 Beginner 16 Intermediate 8 Advanced

About C++

Top 50 C++ interview questions covering OOP, memory management, STL, templates, smart pointers, move semantics, concurrency, and modern C++17/20 features. Companies hiring for C++ roles test this knowledge at every stage — from first-round screens that check the basics to final-round conversations about real-world trade-offs.

What to Expect in a C++ Interview

Expect a mix of conceptual and practical C++ questions: clear definitions and core-concept checks for junior roles, hands-on scenario questions for mid-level roles, and architecture or trade-off discussions for senior roles. Interviewers usually move from foundational topics toward the kind of problems you'd actually face on the job.

How to Use This Guide

Work through the C++ questions in order — Beginner, then Intermediate, then Advanced — so each concept builds on the last. Every question has its own page; bookmark the ones that trip you up and revisit them the day before your interview.

Curated by Tech Baithak Editorial Team · Last updated: May 2026

Beginner 20 questions

Core concepts every C++ developer must know.

01 What is C++ and how does it differ from C? 02 What are the four pillars of OOP in C++? 03 What is a class and an object in C++? 04 What are constructors and destructors in C++? 05 What is the difference between new/delete and malloc/free in C++? 06 What are pointers and references in C++? 07 What is function overloading in C++? 08 What is inheritance in C++? 09 What are virtual functions and polymorphism in C++? 10 What are access specifiers in C++? 11 What is the Standard Template Library (STL)? 12 What are templates in C++? 13 What are smart pointers in C++? 14 What is the difference between stack and heap memory in C++? 15 What are namespaces in C++? 16 What are lambda expressions in C++? 17 What is the const keyword in C++? 18 What is RAII in C++? 19 What is exception handling in C++? 20 What are iterators in C++?

Intermediate 16 questions

Practical knowledge for developers with hands-on experience.

01 What is move semantics in C++? 02 What are lvalues and rvalues in C++? 03 What is the Rule of Three/Five/Zero in C++? 04 What is template specialization and SFINAE in C++? 05 What is std::vector and how does it work internally? 06 What is std::map vs std::unordered_map? 07 What is operator overloading in C++? 08 What is multithreading in C++? 09 What is the difference between shallow copy and deep copy? 10 What are static members in C++? 11 What are the differences between struct and class in C++? 12 What is type casting in C++? 13 What are abstract classes and interfaces in C++? 14 What is std::string and common string operations? 15 What are function pointers and std::function in C++? 16 What are design patterns commonly used in C++?

Advanced 8 questions

Deep expertise questions for senior and lead roles.

01 What is undefined behavior in C++ and how do you avoid it? 02 What is template metaprogramming in C++? 03 What are C++20 features? 04 What is memory alignment and padding in C++? 05 What is the C++ memory model and atomic operations? 06 What are C++ optimization techniques? 07 What is Variadic Templates and Parameter Packs? 08 What is the PIMPL idiom in C++?

Back to All Topics 44 questions total