在 python 开始游戏时遇到问题。游戏永远不会开始，并出现以下错误

Question

在 python 中，我正在尝试创建一个简单的游戏，玩家可以在其中选择下一步要去的洞穴，同时尽量避开 wumpus。在设置初始洞穴结构时，它以某种方式停止并且永远不会开始游戏，并出现以下错误：

Traceback (most recent call last):
  File "/Users/JPagz95/Documents/Hunt_the_Wumpus_3.py", line 80, in <module>
    link_caves()
  File "/Users/JPagz95/Documents/Hunt_the_Wumpus_3.py", line 28, in link_caves
    this_cave = choose_cave(visited_caves)
  File "/Users/JPagz95/Documents/Hunt_the_Wumpus_3.py", line 50, in choose_cave
    cave_number = choice(cave_list)
  File "/Users/JPagz95/anaconda/lib/python3.5/random.py", line 253, in choice
    i = self._randbelow(len(seq))
KeyboardInterrupt

这是我当前的游戏代码。感谢您的帮助:)

from random import choice

cave_numbers = [x for x in range(20)]
unvisited_caves = [x for x in range(20)]
visited_caves = []

def setup_caves(cave_numbers):
    """ create a starting list of caves """
    caves = []
    for number in cave_numbers:
        caves.append(number)
    return caves

def visit_cave(cave_number):
    """ mark a cave as visited """
    visited_caves.append(cave_number)
    unvisited_caves.remove(cave_number)

def print_caves():
    """ print out the current cave structure """
    for number in cave_numbers:
        print (number, ":", caves[number])
    print ('----------')

def link_caves():
    """ make sure all of the caves are connected with two way tunnels"""
    while unvisited_caves != []:
        this_cave = choose_cave(visited_caves)
        next_cave = choose_cave(unvisited_caves)
    create_tunnel(this_cave, next_cave)
    visit_cave(next_cave)

def create_tunnel(cave_from, cave_to):
    """ create a tunnel between cave_from and cave_to """
    caves[cave_from].append(cave_to)
    caves[cave_to].append(cave_from)

def finish_caves():
    """ link the rest of the caves with one way tunnels """
    for caves in cave_numbers:
        while len(caves) < 3:
            passage_to = choose_cave(cave_numbers)
            caves[cave].append(passage_to)

def choose_cave(cave_list):
    """ pick a cave from a list, provided that the
    cave has less than 3 tunnels """
    cave_number = choice(cave_list)
    while len(caves) >= 3:
        cave_number = choice(cave_list)
    return cave_number

def print_location(player_location):
    """ tell the player about where they are """
    print ("You are in a cave ", player_location)
    print ("From here you can see caves: ")
    print (caves[player_location])
    if wumpus_location in caves[player_location]:
        print ("I smell a wumpus!")

def get_next_location():
    """ Get the player's next location """
    print ("Which cave next?")
    player_input = input(">")
    if (not player_input.isdigit() or
        int(player_input) not in
            caves[player_location]):
        print (player_input + "?")
        print ("That's not a direction I can see!")
        return none
    else:
        return int(player_input)

caves = setup_caves(cave_numbers)

visit_cave(0)
print_caves()
link_caves()
print_caves()
finish_caves()

wumpus_location = choice(cave_numbers)
player_location = choice(cave_numbers)
while player_location == wumpus_location:
    player_location = choice(cave_numbers)

print ("Welcome to Hunt the Wumpus!")
print ("You can see ", len(cave_numbers), " caves")
print ("To play, just type the number")
print ("of the cave you wish to enter next")

while True:
    print_location(player_location)
    new_location = get_next_location()
    if new_location != None:
        player_location = new_location
    if player_location == wumpus_location:
        print ("Aargh! You got eaten by a wumpus!")

Answer 1

第一个：

visited_caves = []

然后：

link_caves()

然后：

this_cave = choose_cave(visited_caves)

然后：

cave_number = choice(cave_list)

您正在向 random.choice() 发送一个空的 list，但失败了。

将 link_caves() 更改为仅处理 non-empty lists:

def link_caves():
    """ make sure all of the caves are connected with two way tunnels"""
    if not (visited_caves and unvisited_caves):
        return
    this_cave = choose_cave(visited_caves)
    next_cave = choose_cave(unvisited_caves)
    create_tunnel(this_cave, next_cave)
    visit_cave(next_cave)

请注意，如果此函数没有向 random.choice() 传递无效参数，它就会卡住，因为它使用了条件永远不会改变的 while 循环。我注意到您也在 choose_cave() 和 while len(caves) >= 3: cave_number = choice(cave_list) 中执行此操作。这个特定的片段将检查 caves 的长度，如果是 >= 3，则从 cave_list 中选择一个随机洞穴。然后它会检查 caves 的长度，找到它和以前一样，选择一个随机的洞穴等等，永远。也许您希望 random.choice() 从传递的序列中删除其选定的项目。它不会那样做。如果需要，您可以通过多种方式将其删除，例如在随机选择 cave_number.

后执行 caves.remove(cave_number)

请记住，除了提示您问题的错误和我已经指出的其他错误之外，您的代码中可能还有其他错误。

Answer 2

TigerhawkT3 的详细回答。

我最近查看了此代码的一个版本，您可能可以通过一个小的更改来解决一个问题。修复 link_caves() 函数中的拼写错误，方法是缩进最后两行，使它们位于 'while' 循环内：

def link_caves():
    """ make sure all of the caves are connected with two way tunnels"""
    while unvisited_caves != []:
        this_cave = choose_cave(visited_caves)
        next_cave = choose_cave(unvisited_caves)
        create_tunnel(this_cave, next_cave)
        visit_cave(next_cave)

该更改应创建所需的隧道，并且每次循环都会调用 visit_cave()。 visit_cave() 的最后一行从 unvisited_caves 列表中删除了正确的洞穴，正如 TigerhawkT3 提到的那样，这是必要的。

您确实还有一些问题需要解决，以完成初始化并让游戏进入运行。

追溯语句将告诉您从哪里开始查找。

您可以添加打印语句来显示洞穴列表，以帮助您在代码挂起之前进行调试。

如果将洞穴数量从 20 改为 4-5 之类的小值，调试时输出可能更易于查看。

在 python 开始游戏时遇到问题。游戏永远不会开始，并出现以下错误

Having trouble starting the game in python. The game never starts and the error below shows up

python

python-3.5