Rock Paper Scissors: Implement a Multi-Round Game Engine with Stats Tracking

Question

## Round 1 - Coding

## Problem

Implement a Rock Paper Scissors game engine. Support two players (human or bot), track wins/losses/draws per player, and return a match summary after `N` rounds.

```python
class RPSGame:
    MOVES = {"rock", "paper", "scissors"}

def __init__(self, rounds: int):
        ...
    def play_round(self, move1: str, move2: str) -> str:
        # returns "player1", "player2", or "draw"
        ...
    def get_stats(self) -> dict:
        # {"player1": {"wins":int,"losses":int,"draws":int},
        #  "player2": {...}, "rounds_played": int}
        ...
    def winner(self) -> str:
        # "player1", "player2", or "tie" after all rounds
        ...
```

## Example

```
game = RPSGame(rounds=3)
game.play_round("rock", "scissors")   -> "player1"
game.play_round("paper", "paper")     -> "draw"
game.play_round("scissors", "rock")   -> "player2"
game.get_stats()
# -> {"player1":{"wins":1,"losses":1,"draws":1},
#     "player2":{"wins":1,"losses":1,"draws":1}, "rounds_played":3}
game.winner() -> "tie"
```

## Follow-ups

1. How would you add Rock Paper Scissors Lizard Spock? What data structure best represents the win/loss matrix?
2. Implement a simple bot strategy: always play the move that beat the opponent's last move.
3. How do you validate that moves are legal and handle invalid input gracefully?
4. How would you serialize and restore game state mid-match?

Rock Paper Scissors: Implement a Multi-Round Game Engine with Stats Tracking

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