Question

我有一个作业问题，用字典中的其他单词替换用户输入。当我编写一个for循环时，可以看到第一次迭代正确地替换了关键字，但是第二次迭代替换了字典中的下一个关键字。问题是第一次迭代没有保存或被覆盖。我不确定是什么原因导致的，并且我的代码可能会改变什么？

def main():
    #Get a phrase from the user
    print('')
    phrase = input('Enter a phrase: ')
    checkPhase(phrase)

def checkPhase(phrase):
    #Define the simple thesaurus    
    thesaurus = {
        'Happy': 'Glad',
        'sad' : 'bleak'
    }

    for key in thesaurus:
        old_word = key
        new_word = thesaurus[key]
        print(old_word) #used to help troubleshoot
        print(new_word) #used to help troubleshoot 
        new_phrase = phrase.replace(old_word,new_word)
        print(new_phrase) #used to show phrase after each iteration for troubleshooting

    print(new_phrase)

main()

Answer 1

问题是结果在循环中不断被覆盖。而是在循环之前初始化结果：

def checkPhase(phrase):
    #Define the simple thesaurus    
    thesaurus = {
        'Happy': 'Glad',
        'sad' : 'bleak'
    }

    new_phrase = phrase # <-- init
    for key in thesaurus:
        old_word = key
        new_word = thesaurus[key]
        print(old_word) #used to help troubleshoot
        print(new_word) #used to help troubleshoot 
        new_phrase = new_phrase.replace(old_word,new_word) # <-- modify
        print(new_phrase) #used to show phrase after each iteration for troubleshooting

    print(new_phrase)

用循环替换关键字，但是循环覆盖先前的迭代

1 个答案: