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🧩 Challenges · C++

Build it, break it, predict it, or recall it. Pick a challenge and prove you've got it.

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bug hunt loops

debug
easy medium hard

bug hunt memory

debug
easy medium hard

bug hunt objects

debug
easy medium hard

predict operators and branches

predict
easy medium hard

predict call results

predict
easy medium hard

predict loop output

predict
easy medium hard

predict algorithm result

predict
easy medium hard

predict pointer arithmetic

predict
easy medium hard

recall integer arithmetic

recall
easy medium hard

recall reading input

recall
easy medium hard

recall function rules

recall
easy medium hard

recall reference rules

recall
easy medium hard

recall choosing an owner

recall
easy medium hard

recall rule of five

recall
easy medium hard

recall iterator invalidation

recall
easy medium hard

recall which tool for which bug

recall
easy medium hard

recall warning and standard flags

recall
easy medium hard

recall old way memory ownership

recall
easy medium hard

build a counting loop

construct
easy medium hard

build a running total

construct
easy medium hard

build a filter loop

construct
easy medium hard

build a helper function

construct
easy medium hard