python - 字符串在不应该的情况下发生变化&运行问题

Question

快速概述一下它的作用。生成由用户猜测的数字和 2 个符号(+ 和 *)组成的 secret 字符串。我猜是刽子手。我已经解决了所有其他问题，现在只剩一个半了。我是新手。

首先，一个问题是有时运行它(在 IDLE 中使用 F5)不会显示任何内容。只需“>>”，我就必须关闭 shell 并重新运行它。

其次，在赢得并拒绝再次玩游戏的提议后，它仍然要求输入猜测。我想 while 循环仍然会运行，那么我怎样才能停止它呢？

可能还有其他问题我忽略了，但我已经稍微检查了一下，一切似乎都正常。如果有任何改进的建议(但不要太先进)，请随时指出!

这就是我所拥有的:

from random import randint, choice
maxguesses = 11                                     
wins = 0                                            
losses = 0                                          
points = 0                                          
games = 0                                           
numguesses = 0                                      
allowed = ('0','1','2','3','4','5','6','7','8','9','0','+','*')

guesses = ''                                        
def genform():                                      
    global secret                                   
    global guesses
    global maxguesses
    sym = choice(['++','**','+*','*+'])             
    num = ''                                        
    max = randint(3,9)                             
    for i in range(max):                           
        num = num + str(randint(0,9))               
    secret = sym + num                              
    guesses = ''
    maxguesses = len(secret)+2                      
    return secret                                   

def evaluate(b):
    global evaluated
    evaluated = ''
    s1 = secret[0]
    s2 = secret[1]
    for i in range(2,len(secret)-1):
        evaluated = evaluated + secret[i]
        if (i%2 == 0):
            evaluated = evaluated + s1
        else:
            evaluated = evaluated + s2
    evaluated = evaluated + secret[-1]
    return evaluated

letters = set()
partial = ''
def takeguess(ch):
global numguesses, points, games, wins, partial, guesses
numguesses = numguesses + 1                              
print 'Remaining Guesses: ' + str(maxguesses-numguesses)
if (ch in partial) or (ch in guesses):                      
    print "\nYou've already guessed '%s'. Try again: " % ch
elif ch not in secret:
    guesses = guesses + ch
    print 'Wrong, guess again.'
elif ch in secret:                                         
    letters.add(ch)                                        
    print "\nGood guess, it's in the secret formula!"
    partial = ''.join([l if l in letters else '-' for l in secret])
    print 'Formula so far: ' + partial
    if partial == secret:                                   
        print 'You win!'
        wins = wins + 1
        points = points + 2
        games = games + 1
        bonus = raw_input("Evaluate the formula for 10 bonus points: ") 
        if bonus == str(eval(evaluate(secret))):                        
            points = points + 10
            print "That's correct! +10 points."
            print eval(evaluate(secret)) #REMOVE AFTER
            play_again()
        else:                                              
            print "That's incorrect. The right answer is", eval(evaluate(secret))
            play_again()

def play_again():
global numguesses, guesses, partial, letters
letters = set()
    if points < 2:
        print "\nYou don't have enough points to play again.\nGames Played: " + str(games) + '\nPoints: ' + str(points)
    else:        
        ans = raw_input('Would you like to play again? [y/n] ')
        if ans in ('yY'):
            numguesses = 0
            guesses = ''
            partial = ''
            play()
        elif ans in ('nN'):
            print '\nOkay, goodbye.\nWins: ' + str(wins) + '\nLosses: ' + str(losses) + '\nPoints: ' + str(points)
        else:
            print 'Invalid input.'
            play_again()

def play():
    global numguesses, guesses, partial, points, games, losses
    genform()
    print 'Unsolved formula: ' + ('-'*len(secret))
    print 'You have ' + str(maxguesses) + ' guesses.'
    print secret #REMOVE AFTER
    while (numguesses < maxguesses):
        guess = raw_input('\nEnter a guess: ')    # Receive guess
        if guess not in allowed:                # Check if valid
            print '\nInvalid guess, please enter a single digit, *, or +. Try again: '  
        elif partial != secret:
            takeguess(guess)
            print guesses # REMOVE AFTER
        if numguesses == maxguesses:
            points = points - 2
            games = games + 1
            losses = losses + 1
            print 'Sorry, you lose. The answer is: ' + secret
            play_again()
            return

print 'Welcome to hangman!\n'
play()

Answer 1

这段代码最大的问题是你到处使用全局变量；如果您将值存储在 python 对象中并在每次开始新游戏时初始化您的对象，效果会更好。

要修复您现在使用的内容，您需要在 play_again() 函数中初始化 letters...

def play_again():
    global numguesses, guesses, partial
    global letters
    letters=set()   # Reset letters to be empty
    if points < 2:
        print "\nYou don't have enough points to play again.\nGames Played: " + str(games) + '\nPoints: ' + str(points)
    else:
        ans = raw_input('Would you like to play again? [y/n] ')
        if ans in ('yY'):
            numguesses = 0
            guesses = ''
            partial = ''
            play()
        elif ans in ('nN'):
            print '\nOkay, goodbye.\nWins: ' + str(wins) + '\nLosses: ' + str(losses) + '\nPoints: ' + str(points)
        else:
            print 'Invalid input.'
            play_again()