Live coding
C++ Interview Copilot
C++ interviews are as much about ownership and lifetime as about algorithms — the code has to be correct, and it has to be correct about who frees what.
The round
What a C++ interview actually looks like
C++ screens at trading firms, game studios and systems teams tend to be strict about details a scripting-language round would forgive. You will be asked to write a small class and then defend its copy and move behaviour, or to pick an STL container and justify it against the access pattern. Undefined behaviour is a live topic rather than a footnote.
What you get back
Answers use RAII by default: `unique_ptr` where ownership is exclusive, references where nothing is owned, and raw pointers only where the question is about them. Move constructors and assignment appear when the rule of five applies, and the answer says which rule it is following. Every container choice comes with its complexity and its invalidation rules, because the follow-up is usually about iterator invalidation.
Example prompts
Questions people are actually asked
Send the transcript straight to the coding surface, or snip the problem off the screen.
Implement a class that owns a buffer and follows the rule of five.
Which container for frequent insertion in the middle, and why?
What does std::move actually do to this object?
Where candidates lose points
C++-specific traps
Iterator invalidation
Erasing while iterating is the canonical C++ interview bug, and each container invalidates differently. Naming the rule for the container you chose is the answer.
Treating move as a transfer
std::move is a cast, not an operation. Candidates who describe it as moving data are answering the question the interviewer set to catch exactly that.
Missing virtual destructors
Deleting a derived object through a base pointer without one is undefined behaviour, and it is a standard follow-up to any inheritance question.
Three surfaces
One workspace, three kinds of round
Chat
Behavioral rounds and the “tell me about a time” half of a technical screen, in your own voice.
Live coding
A structured solution with the reasoning attached, so you can talk through the code while you write it.
System design
Architecture answers with the diagram rendered inline, not described in prose.
Choosing a model
Keep reading
Related
C Interview Copilot
Live help for C interviews: pointer arithmetic, manual memory management, and answers that are explicit about undefined behaviour.
Rust Interview Copilot
Live help for Rust interviews: ownership and lifetimes explained as you go, plus solutions that compile rather than fight the borrow checker.
C# Interview Copilot
Live help for C# interviews: async/await answered precisely, LINQ deferred execution, and solutions written the way a .NET reviewer expects.
System design copilot
Architecture rounds with the diagram rendered inside the answer.
Platform setup: hackerrank · codesignal