Battleship Game Implementation

AI-Assisted Coding Round

In this problem you will build a simplified Battleship game step by step. You have access to an AI autocomplete tool — use it to speed up your implementation, but make sure the logic is correct.

Overview

Implement a Battleship class that manages a single-player game board. The board is an n x n grid where ships can be placed and shots can be fired.

• Ships are represented as a list of (row, col) coordinates they occupy.
• A shot hits if it lands on a ship coordinate that hasn't been hit yet.
• The game tracks the state of every cell: 'water', 'ship', 'hit', or 'miss'.

Work through Parts A, B, and C in order. Each part builds on the previous one.

Part A — Board Setup

Implement the constructor and place_ship method:

• __init__(self, n: int) — Create an n x n board. All cells start as 'water'.
• place_ship(self, coordinates: List[List[int]]) -> bool — Place a ship on the board. Each element is [row, col]. Return True if placement is valid (all cells are 'water' and within bounds), False otherwise. On success, mark those cells as 'ship'.

Part B — Shot Logic

Implement the take_shot method:

• take_shot(self, row: int, col: int) -> str — Fire at (row, col). Returns:
  • 'hit' if the cell is 'ship' (mark it 'hit')
  • 'miss' if the cell is 'water' (mark it 'miss')
  • 'already_taken' if the cell is 'hit' or 'miss'
  • 'invalid' if out of bounds

Part C — Game State

Implement helper methods:

• get_board_state(self) -> List[List[str]] — Return the full board as a 2D list of cell states.
• all_ships_sunk(self) -> bool — Return True if no 'ship' cells remain on the board.
• shots_taken(self) -> int — Return total number of shots fired (hits + misses).