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🧩 Challenges · Java

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

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bug hunt basics

debug
easy medium hard

bug hunt objects

debug
easy medium hard

predict loop output

predict
easy medium hard

predict stream result

predict
easy medium hard

recall numbers and casts

recall
easy medium hard

recall operators and precedence

recall
easy medium hard

recall string essentials

recall
easy medium hard

recall collections and costs

recall
easy medium hard

recall functional interfaces

recall
easy medium hard

recall stream operations

recall
easy medium hard

recall exceptions reference

recall
easy medium hard

recall maven lifecycle

recall
easy medium hard

recall http status codes

recall
easy medium hard

recall gc and jit

recall
easy medium hard

recall module directives

recall
easy medium hard

recall design principles and patterns

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