## Problem Build the core logic and frontend for a card-matching memory game. An NxM grid of face-down cards hides N*M/2 pairs. Players flip two cards per turn; a match keeps them face-up, a mismatch flips them back after a short delay. ```ts type Card = { id: number; pairId: number; flipped: boolean; matched: boolean }; class MemoryGame { constructor(public readonly cards: Card[]) {} flip(cardId: number): 'wait' | 'match' | 'no_match' | 'already_flipped' { ... } get moveCount(): number { ... } get isComplete(): boolean { ... } reset(): void { ... } } function createDeck(pairs: number): Card[] { ... } // shuffles cards ``` **Requirements:** Only 2 cards can be in the "pending" state at once. Enforce a delay before non-matching cards are flipped back. ## Follow-ups 1. How do you prevent the user from clicking a third card while the mismatch delay is running? 2. How would you implement the shuffle to guarantee no card is adjacent to its pair? 3. How would you add a high-score board stored in localStorage? 4. How would you animate the flip without using external libraries (CSS 3D transform)?

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Memory Game: Implement the Card-Matching Memory Game with Flip Animation Logic

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Problem Build the core logic and frontend for a card-matching memory game. An NxM grid of face-down cards hides N*M/2 pairs. Players flip two cards per turn; a match keeps them face-up, a mismatch flips them back after a short delay. Requirements: Only 2 cards can be in the "pending" state at once. Enforce a delay before non-matching cards are flipped back. Follow-ups How do you prevent the user from clicking a third card while the mismatch delay is running? How would you implement the shuffle t…

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Memory Game: Implement the Card-Matching Memory Game with Flip Animation Logic

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