Pick your duration, number of questions, and the mix of multiple choice, fill-in-the-blank, and full coding problems. Coding problems actually compile and run your C++ through Judge0 — real stdout, real test cases. Every retake shifts toward the questions you got wrong so you stop drilling what you already know.
Set the rules. Every dial is yours.
Here's how you did.
Coding problems compile and run your son's C++ in a sandbox via Judge0. Get a free key at rapidapi.com/judge0-official/api/judge0-ce (free tier = 50 submissions/day, plenty for daily practice since we batch all test cases into one call).