python小练习——2048

今天跟着实验楼的python小项目走了一遍2048小游戏，感觉收获颇丰，

在这里分享一下代码及遇到问题及感悟

首先是跟着实验楼在linux上敲了一遍整体的代码

没有pycharm的自动补全，还得自己注意PEP-8规范，着实写的很累，但很爽

直接在linux记事本上敲代码，难免语法错误频发，其实这都是很不应该的。

在后期调试时也都一一修改并反思了

这个小项目代码不多，适合现阶段去练习，十分推荐，强烈安利

里面涉及到的知识95%都是学过的，只有些许未涉及，但都实验楼代码中都有注释可以参考

1.未涉及知识补充

curse模块：用来在终端上显示图形界面

collection模块中的defaultdict：提供了一个字典的子类defaultdict。可以指定key值不存在时，value的默认值

any（）函数：用于判断给定的可迭代参数 iterable 是否全部为 False，则返回 False，如果有一个为 True，则返回 True。

 

2.代码分享

以下是实现的代码

import curses
from random import randrange, choice
from collections import defaultdict
letter_codes = [ord(ch) for ch in 'WASDRQwasdrq']
actions = ['Up', 'Left', 'Down', 'Right', 'Restart', 'Exit']
actions_dict = dict(zip(letter_codes, actions * 2))

def get_user_action(keyboard):
    char = "N"
    while char not in actions_dict:
        char = keyboard.getch()
    return actions_dict[char]


def transpose(field):
    return [list(row) for row in zip(*field)]


def invert(field):
    return [row[::-1] for row in field]

class GameField(object):
    def __init__(self, height=4, width=4, win=2048):
        self.height = height
        self.width = width
        self.win_value = 2048
        self.score = 0
        self.highscore = 0
        self.reset()


    def spawn(self):
        new_element = 4 if randrange(100) > 89 else 2
        (i, j) = choice([(i, j) for i in range(self.width) for j in range(self.height) if self.field[i][j] == 0])
        self.field[i][j] = new_element

    def reset(self):
        if self.score > self.highscore:
            self.highscore = self.score
        self.score = 0
        self.field = [[0 for i in range(self.width)] for j in range(self.height)]
        self.spawn()
        self.spawn()
    def move(self,direction):
        def move_row_left(row):
            def tighten(row):
                new_row = [i for i in row if i != 0]
                new_row += [0 for i in range(len(row) - len(new_row))]
                return new_row

            def merge(row):
                pair = False
                new_row = []
                for i in range(len(row)):
                    if pair:
                        new_row.append(2 * row[i])
                        self.score += 2 * row[i]
                        pair = False
                    else:
                        if i + 1 < len(row) and row[i] == row[i + 1]:
                            pair = True
                            new_row.append(0)
                        else:
                            new_row.append(row[i])
                assert len(new_row) == len(row)
                return new_row
            return tighten(merge(tighten(row)))

        moves = {}
        moves['Left'] = lambda field: [move_row_left(row) for row in field]
        moves['Right'] = lambda field: invert(moves['Left'](invert(field)))
        moves['Up'] = lambda field: transpose(moves['Left'](transpose(field)))
        moves['Down'] = lambda field: transpose(moves['Right'](transpose(field)))

        if direction in moves:
            if self.move_is_possible(direction):
                self.field = moves[direction](self.field)
                self.spawn()
                return True
            else:
                return False

    def is_win(self):
        return any(any(i >= self.win_value for i in row) for row in self.field)

    def is_gameover(self):
        return not any(self.move_is_possible(move) for move in actions)

    def move_is_possible(self, direction):
        def row_is_left_movable(row):

            def change(i):
                if row[i] == 0 and row[i + 1] != 0:
                    return True
                if row[i] != 0 and row[i + 1] == row[i]:
                    return True
                return False

            return any(change(i) for i in range(len(row) - 1))

        check = {}
        check['Left'] = lambda field: any(row_is_left_movable(row) for row in field)
        check['Right'] = lambda field: check['Left'](invert(field))
        check['Up'] = lambda field: check['Left'](transpose(field))
        check['Down'] = lambda field: check['Right'](transpose(field))

        if direction in check:
            return check[direction](self.field)
        else:
            return False

    def draw(self, screen):
        help_string1 = '(W)Up (S)Down (A)Left (D)Right'
        help_string2 = '     (R)Restart (Q)Exit      '
        gameover_string = '           GAME OVER      '
        win_string = '          YOU WIN!       '

        def cast(string):
            screen.addstr(string + '
')


        def draw_hor_separator():
            line = '+' + ('+------' * self.width + '+')[1:]
            cast(line)


        def draw_row(row):
            cast(''.join('|{: ^5} '.format(num) if num > 0 else '|      ' for num in row) + '|')

        screen.clear()
        cast('SCORE: ' + str(self.score))
        if 0 != self.highscore:
            cast('HIGHSCORE: ' + str(self.highscore))

        for row in self.field:
            draw_hor_separator()
            draw_row(row)
        draw_hor_separator()


        if self.is_win():
            cast(win_string)
        else:
            if self.is_gameover():
                cast(gameover_string)
            else:
                cast(help_string1)
        cast(help_string2)

def main(stdscr):
    def init():
        game_field.reset()
        return 'Game'

    def not_game(state):
        game_field.draw(stdscr)
        action = get_user_action(stdscr)
        responses = defaultdict(lambda: state)
        responses['Restart'], responses['Exit'] = 'Init', 'Exit'
        return responses[action]

    def game():
        game_field.draw(stdscr)
        action = get_user_action(stdscr)

        if action == 'Restart':
            return 'Init'
        if action == 'Exit':
            return 'Exit'
        if game_field.move(action):  # move successful
            if game_field.is_win():
                return 'Win'
            if game_field.is_gameover():
                return 'Gameover'
        return 'Game'


    state_actions = {
            'Init': init,
            'Win': lambda: not_game('Win'),
            'Gameover': lambda: not_game('Gameover'),
            'Game': game
        }
    curses.use_default_colors()

    game_field = GameField(win=2048)


    state = 'Init'

    while state != 'Exit':
        state = state_actions[state]()

curses.wrapper(main)

3.调试结果

由于是在linux记事本下直接敲代码，没有pycharm的自动补全和时时提醒错误标黄，语法错误犯了很多

在调试中才会发现，这其实是很不应该的

在对应文件夹下 python3 2048.py

然后开始错误频发，不停的回去调试

调试完成并运行成功

 

在终端操作通关游戏

同样 又在pycharm上敲了一遍 并在mac的终端上运行了

 实验楼python2048地址：https://www.shiyanlou.com/courses/368

后面还有附上一份实验楼的用面向对象重构的代码一份

# -*- coding: utf-8 -*-
import random
import curses
from itertools import chain


class Action(object):

    UP = 'up'
    LEFT = 'left'
    DOWN = 'down'
    RIGHT = 'right'
    RESTART = 'restart'
    EXIT = 'exit'

    letter_codes = [ord(ch) for ch in 'WASDRQwasdrq']
    actions = [UP, LEFT, DOWN, RIGHT, RESTART, EXIT]
    actions_dict = dict(zip(letter_codes, actions * 2))

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

    def get(self):
        char = "N"
        while char not in self.actions_dict:
            char = self.stdscr.getch()
        return self.actions_dict[char]


class Grid(object):

    def __init__(self, size):
        self.size = size
        self.cells = None
        self.reset()

    def reset(self):
        self.cells = [[0 for i in range(self.size)] for j in range(self.size)]
        self.add_random_item()
        self.add_random_item()

    def add_random_item(self):
        empty_cells = [(i, j) for i in range(self.size) for j in range(self.size) if self.cells[i][j] == 0]
        (i, j) = random.choice(empty_cells)
        self.cells[i][j] = 4 if random.randrange(100) >= 90 else 2

    def transpose(self):
        self.cells = [list(row) for row in zip(*self.cells)]

    def invert(self):
        self.cells = [row[::-1] for row in self.cells]

    @staticmethod
    def move_row_left(row):
        def tighten(row):
            new_row = [i for i in row if i != 0]
            new_row += [0 for i in range(len(row) - len(new_row))]
            return new_row

        def merge(row):
            pair = False
            new_row = []
            for i in range(len(row)):
                if pair:
                    new_row.append(2 * row[i])
                    # self.score += 2 * row[i]
                    pair = False
                else:
                    if i + 1 < len(row) and row[i] == row[i + 1]:
                        pair = True
                        new_row.append(0)
                    else:
                        new_row.append(row[i])
            assert len(new_row) == len(row)
            return new_row
        return tighten(merge(tighten(row)))

    def move_left(self):
        self.cells = [self.move_row_left(row) for row in self.cells]

    def move_right(self):
        self.invert()
        self.move_left()
        self.invert()

    def move_up(self):
        self.transpose()
        self.move_left()
        self.transpose()

    def move_down(self):
        self.transpose()
        self.move_right()
        self.transpose()

    @staticmethod
    def row_can_move_left(row):
        def change(i):
            if row[i] == 0 and row[i + 1] != 0:
                return True
            if row[i] != 0 and row[i + 1] == row[i]:
                return True
            return False
        return any(change(i) for i in range(len(row) - 1))

    def can_move_left(self):
        return any(self.row_can_move_left(row) for row in self.cells)

    def can_move_right(self):
        self.invert()
        can = self.can_move_left()
        self.invert()
        return can

    def can_move_up(self):
        self.transpose()
        can = self.can_move_left()
        self.transpose()
        return can

    def can_move_down(self):
        self.transpose()
        can = self.can_move_right()
        self.transpose()
        return can


class Screen(object):

    help_string1 = '(W)up (S)down (A)left (D)right'
    help_string2 = '     (R)Restart (Q)Exit'
    over_string = '           GAME OVER'
    win_string = '          YOU WIN!'

    def __init__(self, screen=None, grid=None, score=0, best_score=0, over=False, win=False):
        self.grid = grid
        self.score = score
        self.over = over
        self.win = win
        self.screen = screen
        self.counter = 0

    def cast(self, string):
        self.screen.addstr(string + '
')

    def draw_row(self, row):
        self.cast(''.join('|{: ^5}'.format(num) if num > 0 else '|     ' for num in row) + '|')

    def draw(self):
        self.screen.clear()
        self.cast('SCORE: ' + str(self.score))
        for row in self.grid.cells:
            self.cast('+-----' * self.grid.size + '+')
            self.draw_row(row)
        self.cast('+-----' * self.grid.size + '+')

        if self.win:
            self.cast(self.win_string)
        else:
            if self.over:
                self.cast(self.over_string)
            else:
                self.cast(self.help_string1)

        self.cast(self.help_string2)


class GameManager(object):

    def __init__(self, size=4, win_num=2048):
        self.size = size
        self.win_num = win_num
        self.reset()

    def reset(self):
        self.state = 'init'
        self.win = False
        self.over = False
        self.score = 0
        self.grid = Grid(self.size)
        self.grid.reset()

    @property
    def screen(self):
        return Screen(screen=self.stdscr, score=self.score, grid=self.grid, win=self.win, over=self.over)

    def move(self, direction):
        if self.can_move(direction):
            getattr(self.grid, 'move_' + direction)()
            self.grid.add_random_item()
            return True
        else:
            return False

    @property
    def is_win(self):
        self.win = max(chain(*self.grid.cells)) >= self.win_num
        return self.win

    @property
    def is_over(self):
        self.over = not any(self.can_move(move) for move in self.action.actions)
        return self.over

    def can_move(self, direction):
        return getattr(self.grid, 'can_move_' + direction)()

    def state_init(self):
        self.reset()
        return 'game'

    def state_game(self):
        self.screen.draw()
        action = self.action.get()

        if action == Action.RESTART:
            return 'init'
        if action == Action.EXIT:
            return 'exit'
        if self.move(action):
            if self.is_win:
                return 'win'
            if self.is_over:
                return 'over'
        return 'game'

    def _restart_or_exit(self):
        self.screen.draw()
        return 'init' if self.action.get() == Action.RESTART else 'exit'

    def state_win(self):
        return self._restart_or_exit()

    def state_over(self):
        return self._restart_or_exit()

    def __call__(self, stdscr):
        curses.use_default_colors()
        self.stdscr = stdscr
        self.action = Action(stdscr)
        while self.state != 'exit':
            self.state = getattr(self, 'state_' + self.state)()


if __name__ == '__main__':
    curses.wrapper(GameManager())