I went straight to writing a classify function and completely missed that they wanted a class hierarchy.
Start by clarifying the game rules and custom hand rankings, then outline an object-oriented design with classes for Card, Deck, Hand, Player, and Game. Focus on extensibility and separation of concerns, and discuss how to implement the evaluate function using the custom strength ordering.
Pro tip: Demonstrate awareness of trade-offs: e.g., using a strategy pattern for hand evaluation allows easy addition of new hand types without modifying existing code. Also, mention testability and edge cases like ties and invalid inputs.
Ask questions to understand the game rules, custom hand rankings, and strength ordering. Confirm the expected input/output of the evaluate function.
Identify core classes (Card, Deck, Hand, Player, Game) and their responsibilities. Consider using interfaces or abstract classes for extensibility.
Define a HandEvaluator that encapsulates the custom ranking logic. Use a strategy pattern or comparator to handle non-standard strength ordering.
Design the Game class to manage players, deal cards, and call the evaluator. Ensure the evaluate function returns the correct winner or tie.
Explain design choices (e.g., composition over inheritance) and how to test edge cases. Mention potential extensions like adding new hand types.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
Start by clarifying the current design and the pain points of adding new hand types. Then propose a polymorphic, data-driven architecture where each hand type is a self-contained module implementing a common interface, and the evaluator/classifier use a registry or plugin system to discover and apply them. Emphasize that the core logic remains closed for modification but open for extension, and discuss trade-offs like performance and complexity.
Pro tip: Mention that you'd enforce the contract with automated tests that run against all registered hand types, ensuring new additions don't break existing behavior. This shows you think about maintainability and regression safety, not just extensibility.
Ask about the existing hand types, how they are evaluated, and what 'no changes' means (e.g., no code changes vs. no recompilation). Identify the extension points and constraints.
Propose an interface (e.g., HandType) with methods like matches(cards) and evaluate(cards) that all hand types must implement. This decouples the evaluator from concrete implementations.
Use a registry (e.g., a map of hand type identifiers to instances) that is populated at startup or dynamically via reflection/configuration. The evaluator iterates over registered hand types without knowing their specifics.
Refactor the evaluator to accept a collection of hand types and return the best match. The classifier should delegate to the evaluator and not contain hand-specific logic.
Address performance implications (e.g., iteration order, early exit), and propose a test suite that validates all hand types against a shared contract to guarantee correctness when adding new ones.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
Explain that the tie-break rule is defined on the original dealt order, so sorting changes the relative order and thus the outcome. Then describe a concrete input where the sorted order produces a different tie-break result than the dealt order, such as a hand with equal ranks but different suits.
Pro tip: Emphasize that the tie-break is a stable, order-dependent operation; sorting is not a valid optimization because it destroys the original sequence. Mention that you would write a test with a hand that has duplicate ranks to catch this bug.
State that the tie-break walks cards right-to-left in the exact order they were dealt, without any sorting. This order is part of the game's specification.
Sorting reorders the cards, so the right-to-left traversal no longer follows the dealt order. This changes which card is considered first, potentially altering the tie-break winner.
Give an input where the dealt order and sorted order differ, such as a hand with two cards of the same rank but different suits. Show that the tie-break result changes after sorting.
Explain that this is a correctness bug, not just an optimization issue. Sorting might seem harmless but violates the specification and can lead to wrong outcomes in edge cases.
Recommend preserving the original order and writing a unit test with duplicate ranks to ensure the tie-break behaves as specified.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
Start by clarifying the existing hand type hierarchy and the insertion point, then propose a minimal, additive change that introduces the new type without modifying existing logic. Emphasize backward compatibility and how you would verify that no existing behavior changes.
Pro tip: Mention that you would add the new type at the end of any enum or constant list to avoid shifting existing values, and use feature flags or versioning if the type affects serialization or APIs.
Ask about the existing hand type representation (enum, class hierarchy, etc.) and where the new type should be inserted. Confirm the ordering and any dependencies.
Determine the exact location in code (e.g., enum, factory, switch statement) where the new type must be added, ensuring it doesn't disrupt existing values or logic.
Introduce the new type by adding a new constant, subclass, or configuration entry, without modifying existing ones. If ordering matters, append at the end or use explicit values.
Adjust any switch statements, comparisons, or factory methods to handle the new type, but only by adding new cases, not altering existing ones.
Run existing tests, add new tests for the new type, and confirm that all previous behaviors remain identical. Use diff tools to ensure only additive changes.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.
Short answer: a single card value mapping at the parsing layer.
Identify the single source of truth for card labels, such as a constant or configuration, and explain how to centralize the logic that maps card values to their display strings. Then describe how to isolate the change by ensuring all other parts of the system depend on an abstraction rather than hardcoded values. Emphasize that the goal is to make the change in one place without affecting consumers.
Pro tip: Mention that you would also add tests around the label generation to ensure the change doesn't break existing behavior, and consider using a feature flag to roll out the change safely.
Locate where card labels are currently defined, such as a constant array or a configuration file. Explain that this should be the only place that needs modification.
Ensure that the logic for converting a card value to its label is encapsulated in a single function or class. This function should be the only place that knows about the label alphabet.
Make sure all consumers of card labels use the abstraction (e.g., a getLabel method) rather than hardcoding values. This decouples the rest of the system from the label details.
Modify the source of truth to include face cards, and run tests to verify that the change is isolated and correct. Consider adding new tests for face cards.
Use feature flags or a gradual rollout to mitigate risk. Monitor for any unexpected issues after deployment.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.