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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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453 challenges matching your filters
Clear topic filter- Multiple ChoiceBeginner
C: extern (b29)
cbeginner - Multiple ChoiceBeginner
C: register
cbeginner - Multiple ChoiceBeginner
Pointer Arithmetic
cbeginner - Multiple ChoiceBeginner
Void Pointer
cbeginner - Multiple ChoiceBeginner
Array vs Pointer
cbeginner - Multiple ChoiceBeginner
String Literal
cbeginner - Multiple ChoiceBeginner
strlen Function
cbeginner - Multiple ChoiceBeginner
strcpy Function
cbeginner - Multiple ChoiceBeginner
strcmp Function
cbeginner - Multiple ChoiceBeginner
strcat Function
cbeginner - Multiple ChoiceBeginner
sprintf Function
cbeginner - Multiple ChoiceBeginner
Buffer Overflow
cbeginner - Multiple ChoiceBeginner
Stack Memory
cbeginner - Multiple ChoiceBeginner
Heap Memory
cbeginner - Multiple ChoiceBeginner
malloc Return
cbeginner - Multiple ChoiceBeginner
free Function
cbeginner - Multiple ChoiceBeginner
Dangling Pointer
cbeginner - Multiple ChoiceBeginner
Memory Leak
cbeginner - Multiple ChoiceBeginner
calloc vs malloc
cbeginner - Multiple ChoiceBeginner
realloc Function
cbeginner - Multiple ChoiceBeginner
Multi-dim Array
cbeginner - Multiple ChoiceBeginner
2D Array Layout
cbeginner - Multiple ChoiceBeginner
Function Declaration
cbeginner - Multiple ChoiceBeginner
Pass by Value
cbeginner - Multiple ChoiceBeginner
Pass by Pointer
cbeginner - Multiple ChoiceBeginner
Recursion in C
cbeginner - Multiple ChoiceBeginner
Header Files
cbeginner - Multiple ChoiceBeginner
Preprocessor Guard
cbeginner - Multiple ChoiceBeginner
#define Macro
cbeginner - Multiple ChoiceBeginner
gcc Compile
cbeginner - Multiple ChoiceBeginner
Segmentation Fault
cbeginner - Multiple ChoiceBeginner
Undefined Behavior
cbeginner - Multiple ChoiceHard
Flexible Array Member
chard - Multiple ChoiceHard
Designated Initializer
chard - Multiple ChoiceHard
Compound Literal
chard - Multiple ChoiceHard
_Generic
chard - Multiple ChoiceHard
_Atomic
chard - Multiple ChoiceHard
_Alignas
chard - Multiple ChoiceHard
_Static_assert
chard - Multiple ChoiceHard
Opaque Pointer
chard - Multiple ChoiceHard
VLA
chard - Multiple ChoiceHard
alloca
chard - Multiple ChoiceHard
Memory Ordering
chard - Multiple ChoiceHard
Duff's Device
chard - Multiple ChoiceHard
X-Macro
chard - Multiple ChoiceHard
Obfuscated C
chard - Multiple ChoiceHard
Strict Aliasing
chard - Multiple ChoiceHard
TLS
chard - Multiple ChoiceHard
CTAD
chard - Multiple ChoiceHard
Nested Function
chard - Multiple ChoiceHard
__attribute__
chard - Multiple ChoiceHard
Integer Promotion
chard - Multiple ChoiceHard
Usual Arithmetic Conversion
chard - Multiple ChoiceHard
Trigraph
chard - Multiple ChoiceHard
Digraph
chard - Multiple ChoiceHard
Locale
chard - Multiple ChoiceHard
Wide Characters
chard - Multiple ChoiceHard
memfrob
chard - Multiple ChoiceHard
C99 vs C89
chard - Multiple ChoiceHard
C11 Additions
chard
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