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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702 challenges matching your filters
- Code AnalysisIntermediate
Trace: Struct Member
canalysisintermediate - Code AnalysisIntermediate
Trace: Switch Fallthrough
canalysisintermediate - Code AnalysisIntermediate
Trace: Nested Ternary
canalysisintermediate - Code AnalysisIntermediate
Trace: Type Promotion
canalysisintermediate - Code AnalysisIntermediate
Trace: Unary Chain
canalysisintermediate - Code AnalysisIntermediate
Trace: Union Size
canalysisintermediate - Code AnalysisIntermediate
Trace: Anonymous Union
canalysisintermediate - Code AnalysisIntermediate
Trace: Array Decay — sizeof
canalysisintermediate - Code AnalysisIntermediate
Trace: Partial Initialization
canalysisintermediate - Code AnalysisIntermediate
Trace: Static Assert
canalysisintermediate - Code AnalysisIntermediate
Trace: Bitfield Width
canalysisintermediate - Code AnalysisIntermediate
Trace: Comma Evaluation
canalysisintermediate - Code AnalysisIntermediate
Trace: Compound Literal
canalysisintermediate - Code AnalysisIntermediate
Trace: Designated Init
canalysisintermediate - Code AnalysisIntermediate
Trace: Div-Mul Rounding
canalysisintermediate - Code AnalysisIntermediate
Trace: Flexible Array
canalysisintermediate - Code AnalysisIntermediate
Trace: Inline Hint
canalysisintermediate - Code AnalysisIntermediate
Trace: Memcmp
canalysisintermediate - Code AnalysisIntermediate
Trace: Modulo Negative
canalysisintermediate - Code AnalysisIntermediate
Trace: Multi-Dim Array
canalysisintermediate - Code AnalysisIntermediate
Trace: Packed Attribute
canalysisintermediate - Code AnalysisIntermediate
Trace: Pointer to Array
canalysisintermediate - Code AnalysisIntermediate
Trace: Pointer Subtraction
canalysisintermediate - Code AnalysisIntermediate
Trace: Restrict
canalysisintermediate - Code AnalysisIntermediate
Trace: Sequence Point
canalysisintermediate - Code AnalysisIntermediate
Trace: Sizeof Side Effects
canalysisintermediate - Code AnalysisIntermediate
Trace: Sprintf Return
canalysisintermediate - Code AnalysisIntermediate
Trace: Static Function
canalysisintermediate - Code AnalysisIntermediate
Trace: Strchr
canalysisintermediate - Code AnalysisIntermediate
Trace: Strcpy Buffer
canalysisintermediate - Code AnalysisIntermediate
Trace: String Literal Mod
canalysisintermediate - Code AnalysisIntermediate
Trace: Strtok State
canalysisintermediate - Code AnalysisIntermediate
Trace: Struct Reorder
canalysisintermediate - Code AnalysisIntermediate
Trace: Token Pasting
canalysisintermediate - Code AnalysisIntermediate
Trace: VLA Sizeof
canalysisintermediate - Code AnalysisIntermediate
Trace: Void Pointer Arithmetic
canalysisintermediate - Code AnalysisIntermediate
Trace: Volatile
canalysisintermediate - Code AnalysisIntermediate
Trace: XOR Swap — Without Temp
canalysisintermediate - Code AnalysisIntermediate
Macro Expansion Trap
code-analysisClanguage - Code AnalysisIntermediate
Post-increment Loop
code-analysisClanguage - Code AnalysisIntermediate
Pointer Arithmetic
code-analysisClanguage - Code AnalysisIntermediate
String Literal Length
code-analysisClanguage - Code AnalysisIntermediate
Ternary Operator
code-analysisClanguage - Code AnalysisIntermediate
Deleting derived through base pointer
cppvirtualdestructorundefined-behavior - Code AnalysisIntermediate
Capture by reference outliving scope
cpplambdacapturedangling - Code AnalysisIntermediate
Dangling reference in std::async
cppasynclambdacapture - Code AnalysisIntermediate
Return local by value
cpprvoreturncode-analysis - Code AnalysisIntermediate
Lambda returning reference to by-value capture
cpplambdadanglingreferences - Code AnalysisIntermediate
Virtual call during destruction
cppvirtualdestructorcode-analysis - Code AnalysisIntermediate
unordered_map pointer survives rehash
cppstlunordered_mapiterator-invalidation - Code AnalysisIntermediate
Reference to vector element across growth
cppstlvectordangling - Code AnalysisIntermediate
Brace init narrowing error
cppaggregate-initnarrowingcode-analysis - Code AnalysisIntermediate
const member mutating through pointer
cppconst-correctnesspointersgotcha - Code AnalysisIntermediate
new[] / delete mismatch
cppundefined-behaviornew-deletecode-analysis - Code AnalysisIntermediate
Range-for over returning-by-value container
cpprange-forlifetimecode-analysis - Code AnalysisIntermediate
Two-mutex lock-order deadlock
cppthreadingdeadlockmutex - Code AnalysisIntermediate
volatile increment not atomic
cppatomicsvolatiledata-race - Code AnalysisIntermediate
Detached thread using this
cppthreadingdanglinglambda - Code AnalysisIntermediate
std::thread destructor terminate
cppthreadingstd-threadcode-analysis - Code AnalysisIntermediate
sizeof object with vptr
cppsizeofvtablecode-analysis
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