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Coding Challenges

5,893 curated questions across every arena — browse by topic, then jump into a live 3-minute battle to put them to the test.

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6 challenges matching your filters

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Code AnalysisIntermediate
Capture by reference outliving scope
cpplambdacapturedangling
Code AnalysisIntermediate
Dangling reference in std::async
cppasynclambdacapture
Code AnalysisIntermediate
Lambda returning reference to by-value capture
cpplambdadanglingreferences
Code AnalysisIntermediate
Detached thread using this
cppthreadingdanglinglambda
Multiple ChoiceIntermediate
Stateless lambda to function pointer
cpplambdafunction-pointer
Multiple ChoiceIntermediate
Generic lambda and auto capture
cpplambdageneric-lambdac++14

Practice now, dominate the arena

Every challenge here is drawn from the live Code Royale pool. Review a question, then head to the arena to answer under pressure against a real opponent — 3-minute matches, Elo ranking, and badge tiers on the line.

Coding Challenges

Capture by reference outliving scope

Dangling reference in std::async

Lambda returning reference to by-value capture

Detached thread using this

Stateless lambda to function pointer

Generic lambda and auto capture

Practice now, dominate the arena