exampleSolver.py

from minesweeper import *


def exampleSolveGame(grid):
    """
    This is an intentionally crappy AI to solve a game on Minesweeper.  It
    may not play well, but it does illustrate the basics of how to code an AI.
    It'll be easiest if you write your own AI in a function like this one, but
    hopefully it'll be better.

    Here's the basic form your function should take.  The input parameter
    `grid' will be a Minefield object (see minesweeper.py for more info):

        def myAwesomeSolveGame(grid):
            while not grid.isSolved():
                <put awesome code here to calculate which row and column coordinates to choose here>

                grid.guess(row, column)
    """

    while not grid.isSolved():
        # This dictionary will map the coordinates of a square to
        # an estimate of the probability that the square has a mine
        # on it.  We start with a baseline probability based on
        # how many mines there in total.
        baselineProbability = grid.nMines() / float(grid.nHidden())
        hiddenSquareProbabilities = dict(((r,c), baselineProbability) for r,c in grid.iterHidden())

        # For each visible square, check if it has a nonzero number of hidden
        # squares surrounding it.  Use the number of mines surrounding the square
        # as well as the number of curenly hidden squares around to update
        # the estimate of the probability that the square has a mine on it.
        for r,c in grid.iterVisible():
            if grid.nHiddenAround(r,c) > 0:
                mineProb = grid.nMinesAround(r,c) / float(grid.nHiddenAround(r,c))
                for r2,c2 in grid.iterNeighbors(r,c):
                    if (r2,c2) in hiddenSquareProbabilities:
                        hiddenSquareProbabilities[(r2,c2)] = max(hiddenSquareProbabilities[(r2,c2)], mineProb)

        # Pick the square with the lowest estimated probability.
        availableSquares = [(prob,(r,c)) for (r,c),prob in hiddenSquareProbabilities.iteritems()]
        availableSquares.sort()
        row, column = availableSquares[0][1]
        grid.guess(row, column)


def main():
    # Set this to True if you want to play a game of Minesweeper with a
    # crappy text interface.  Set this to False if you want to test
    # how good the example AI is (spoiler: not very).
    doYouWantToPlayAGame = False

    if doYouWantToPlayAGame:
        playGame(9, 9, 10)
    else:
        testSolver(exampleSolveGame)

if __name__ == "__main__":
    main()