Challenge Library
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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345 challenges matching your filters
- Code AnalysisHard
Trace: Lost Update
backendanalysishard - Code AnalysisHard
Trace: Retry Storm
backendanalysishard - Code AnalysisHard
Idempotency key flow
backendhard - Code AnalysisHard
Circuit breaker states
backendhard - Code AnalysisHard
Circuit breaker flow
backendhard - Code AnalysisHard
Service discovery flow
backendhard - Code AnalysisHard
Saga orchestration
backendhard - Code AnalysisHard
Refresh token rotation
backendhard - Code AnalysisHard
Cache stampede prevention
backendhard - Code AnalysisHard
Normalization 2NF
backendhard - Code AnalysisHard
Readiness probe
backendhard - Code AnalysisHard
Event sourcing replay
backendhard - Code AnalysisHard
Clean arch dependency rule
backendhard - Code AnalysisHard
Aggregate root
backendhard - Code AnalysisHard
Prometheus counter
backendhard - Code AnalysisHard
Error budget burn
backendhard - Code AnalysisHard
Consumer group rebalance
backendhard - Code AnalysisHard
Stream processing example
backendhard - Code AnalysisHard
CAP trade-off
backendhard - Code AnalysisHard
Heap snapshot analysis
backendhard - Code AnalysisHard
CORS misconfig
backendhard - Code AnalysisHard
JWT none algorithm
backendhard - Code AnalysisHard
Trace: Signed Left Shift
canalysishard - Code AnalysisHard
Trace: char Sign
canalysishard - Code AnalysisHard
Trace: Struct Size
canalysishard - Code AnalysisHard
Trace: Alignof
canalysishard - Code AnalysisHard
Trace: Array Decay
canalysishard - Code AnalysisHard
Trace: Bit Mask
canalysishard - Code AnalysisHard
Trace: Bitwise NOT
canalysishard - Code AnalysisHard
Trace: Popcount Trick
canalysishard - Code AnalysisHard
Trace: Sign Bit Shift
canalysishard - Code AnalysisHard
Trace: XOR Swap
canalysishard - Code AnalysisHard
Trace: Comma Operator
canalysishard - Code AnalysisHard
Trace: Stringify Macro
canalysishard - Code AnalysisHard
Trace: Division by Zero
canalysishard - Code AnalysisHard
Trace: Enum Values
canalysishard - Code AnalysisHard
Trace: Extern Concept
canalysishard - Code AnalysisHard
Trace: Function Pointer
canalysishard - Code AnalysisHard
Trace: Variable Shadow
canalysishard - Code AnalysisHard
Trace: Ifdef
canalysishard - Code AnalysisHard
Trace: Macro Pitfall
canalysishard - Code AnalysisHard
Trace: Pointer Arithmetic
canalysishard - Code AnalysisHard
Trace: Pointer Difference
canalysishard - Code AnalysisHard
Trace: Double Pointer
canalysishard - Code AnalysisHard
Trace: Recursive Factorial
canalysishard - Code AnalysisHard
Trace: Recursive GCD
canalysishard - Code AnalysisHard
Trace: Negative Shift
canalysishard - Code AnalysisHard
Trace: Signed Overflow
canalysishard - Code AnalysisHard
Trace: Static Variable
canalysishard - Code AnalysisHard
Trace: Strcmp Result
canalysishard - Code AnalysisHard
Trace: String Literal Size
canalysishard - Code AnalysisHard
Trace: Struct Padding
canalysishard - Code AnalysisHard
Trace: Typedef
canalysishard - Code AnalysisHard
Trace: Union Access
canalysishard - Code AnalysisHard
Trace: Void Pointer
canalysishard - Code AnalysisHard
Array Decay
code-analysisClanguage - Code AnalysisHard
Const Cast
code-analysisClanguage - Code AnalysisHard
Dangling Pointer
code-analysisClanguage - Code AnalysisHard
Negative Modulo
code-analysisClanguage - Code AnalysisHard
restrict Pointer
code-analysisClanguage
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