为什么这个局部整数不能修改全局常量?

时间:2013-03-19 21:05:10

标签: python

我一直用Python制作这个Hangman游戏。问题出在play_hangman函数中。每当猜测发生时,常数“猜测”增加1。我希望它打印出“%s猜测还剩!”我从全局常量(MAX_GUESSES)中得到%s减去局部常数(猜测)。然而它似乎不起作用,并且当它应该向下增加时它继续吐出“剩下的6个猜测”。有什么建议?

   # CONSTANTS
MAX_GUESSES = 6

# GLOBAL VARIABLES 
secret_word = 'claptrap' 
letters_guessed = []

# From part 3b:
def word_guessed():
    '''
    Returns True if the player has successfully guessed the word,
    and False otherwise.
    '''
    global secret_word
    global letters_guessed
    for i in secret_word:
        if i in letters_guessed:
            continue
        else:
            return False        
    return True


def print_guessed():
    '''
    Prints out the characters you have guessed in the secret word so far
    '''
    global secret_word
    global letters_guessed
    blanklist = []
    for i in secret_word:
        if i in letters_guessed:
            blanklist.append(i)
        else:
            blanklist.append("-")
    blanklist_string = "".join(blanklist)
    return blanklist_string

def play_hangman():
    # Actually play the hangman game
    global secret_word
    global letters_guessed
    global MAX_GUESSES
    # Put the mistakes_made variable here, since you'll only use it in this function
    mistakes_made = 0
    guesses = 0
    guesses_left = MAX_GUESSES - guesses

    while word_guessed() is False:
        print print_guessed()
        print "%s guesses left!" % guesses_left
        letter_choice = raw_input("Choose a letter:")
        if letter_choice not in secret_word:
            mistakes_made += 1
            print "you have made %s mistakes" %mistakes_made
            print "sorry, that is not in the word"
        letters_guessed.append(letter_choice)
        guesses +=1
        print "you have made %s guesses" %guesses
        word_guessed()

    while word_guessed() is True:
        print "Congratulations! You win :)"
        break

2 个答案:

答案 0 :(得分:1)

您需要将guesses_left = MAX_GUESSES - guesses置于while word_guessed() is False:循环内。就像现在一样,您在guesses_left = MAX_GUESSES - guesses时设置guesses == 0,然后仅在循环内更改guesses。这将使guesses_left保持不变。

答案 1 :(得分:1)

您不会重新计算guesses_left。在每次迭代开始时,您必须执行guesses_left = MAX_GUESSES - guesses