game_of_life.py

from time import sleep


class Cell:
    ALIVE = True
    DEAD = False

    def __init__(self, status):
        self.status = status

    def __str__(self):
        if self.status == self.ALIVE:
            return 'O'
        else:
            return '.'

    def next_status(self, neighbors):
        count = sum([1 for n in neighbors if n.status == self.ALIVE])

        if self.status == self.ALIVE:
            return self.ALIVE if (count in [2, 3]) else self.DEAD
        else:
            return self.ALIVE if (count == 3) else self.DEAD


class Grid:
    def __init__(self, seed):
        self.height = len(seed)
        self.width = len(seed[0])
        self.state = []

        for row in seed:
            cells = [Cell(state) for state in row]
            self.state.append(cells)


    def display(self):
        for row in self.state:
            print(' '.join([str(cell) for cell in row]))

    def _neighbors(self, i, j):
        cells = []
        for x in range(max(0, i-1), min(self.height, i+2)):
            for y in range(max(0, j-1), min(self.width, j+2)):
                if x == i and y == j:
                    continue

                cells.append(self.state[x][y])

        return cells

    def update(self):
        new_state = []

        for (i, row) in enumerate(self.state):
            new_row = []

            for (j, cell) in enumerate(row):
                neighbors = self._neighbors(i, j)
                next_cell = Cell(cell.next_status(neighbors))
                new_row.append(next_cell)

            new_state.append(new_row)

        self.state = new_state


if __name__ == '__main__':
    seed = [
        [False, False, False, False, False, False],
        [False, False, False, False, False, False],
        [False, True, True, False, False, False],
        [False, True, True, False, False, False],
        [False, False, False, True, True, False],
        [False, False, False, True, True, False],
        [False, False, False, False, False, False]
    ]
    grid = Grid(seed)

    while True:
        grid.display()
        sleep(1)
        grid.update()