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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147 challenges matching your filters
Clear topic filter- Multiple ChoiceIntermediate
Signed Overflow
cintermediate - Multiple ChoiceIntermediate
Null Pointer Deref
cintermediate - Multiple ChoiceIntermediate
Double Free
cintermediate - Multiple ChoiceIntermediate
Use After Free
cintermediate - Multiple ChoiceIntermediate
Stack Overflow
cintermediate - Multiple ChoiceIntermediate
Signal Handler
cintermediate - Multiple ChoiceIntermediate
setjmp/longjmp
cintermediate - 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 - Multiple ChoiceIntermediate
[C Language] strcpy Writing past array bounds
qaccqa - Multiple ChoiceIntermediate
[C Language] Stack smash Writing past array bounds
qaccqa - Multiple ChoiceIntermediate
[C Language] gets deprecated Writing past array bounds
qaccqa - Multiple ChoiceIntermediate
[C Language] Canary Writing past array bounds
qaccqa - Multiple ChoiceIntermediate
[C Language] ASAN Writing past array bounds
qaccqa - Multiple ChoiceIntermediate
[C Language] Header inclusion Text substitution before compilation
qaccqa - Multiple ChoiceIntermediate
[C Language] define vs inline Text substitution before compilation
qaccqa - Multiple ChoiceIntermediate
[C Language] ifdef DEBUG Text substitution before compilation
qaccqa - Multiple ChoiceIntermediate
[C Language] pragma once Text substitution before compilation
qaccqa - Multiple ChoiceIntermediate
[C Language] Token pasting Text substitution before compilation
qaccqa - Multiple ChoiceIntermediate
[C Language] Simple Create type alias
qaccqa - Multiple ChoiceIntermediate
[C Language] Struct alias Create type alias
qaccqa - Multiple ChoiceIntermediate
[C Language] Function pointer Create type alias
qaccqa - Multiple ChoiceIntermediate
[C Language] Opaque type Create type alias
qaccqa - Multiple ChoiceIntermediate
[C Language] Array type Create type alias
qaccqa
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