Harden collections frequency index
Hard Java arena: HashMap, sorting, and stable tie breakers
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Missing prerequisites: java-easy-collections-frequency
A search service needs the top terms from query logs. You are working inside a Java backend interview lab, and the arena only clears when the result is safe, deterministic, and explainable.
Learn to apply HashMap, sorting, and stable tie breakers in a Java backend interview lab while explaining the invariant, safety constraints, and hidden edge cases.
- Demonstrates HashMap, sorting, and stable tie breakers
- Handles the visible sample and hidden edge cases
- Keeps output deterministic and explainable
- Avoids unsafe dynamic execution
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