Question

我一直在使用Python编写代码，但似乎无法找出错误的位置。如果有人可以提供帮助，或者提供一些提示让我朝着正确的方向前进，那将非常感激。

def find_longest_word(a):

    length = len(a[0])
    word = a[0]
    for i in wordlist:
      if len(i) > length:
          word = (i)
          length = len(i)

    return word, length

def main():

    wordlist = input("Enter a few words and I will find the longest: ").split()
    word, length = find_longest_word(wordlist)
    print (word,"is the longest word that you have listed.")

main()

Answer 1

缺少缩进。
find_longest_word函数wordlist未定义。我们需要在a循环中使用变量for。从for i in wordlist:更改为for i in a:
我使用的是python 2.7，因此使用了raw_input()。

代码：

def find_longest_word(a):

    length = len(a[0])
    word = a[0]
    for i in a:
        if len(i) > length:
            word = i
            length = len(i)

    return word, length

def main():

    wordlist = raw_input("Enter a few words and I will find the longest: ").split()
    word, length = find_longest_word(wordlist)
    print (word,"is the longest word that you have listed.")

main()

输出：

vivek@vivek:~/Desktop/stackoverflow$ python 23.py 
Enter a few words and I will find the longest: 1 234 2344 3 4
('2344', 'is the longest word that you have listed.')

使用集合模块和字典方法。

>>> import collections
>>> msg = "whish word is longest from this msg"
>>> msg.split()
['whish', 'word', 'is', 'longest', 'from', 'this', 'msg']
>>> d = collections.defaultdict(list)
>>> for i in msg.split():
...    d[len(i)].append(i)
... 
>>> d
defaultdict(<type 'list'>, {2: ['is'], 3: ['msg'], 4: ['word', 'from', 'this'], 5: ['whish'], 7: ['longest']})
>>> max(d.keys())
7
>>> d[max(d.keys())]
['longest']
>>>

Answer 2

您的缩进必须是四个空格或功能下的标签，并且必须在整个程序中保持一致。

def find_longest_word(a):

length = len(a[0])
word = a[0]
for i in a:
    if len(i) > length:
        word = (i)
        length = len(i)

return word, length

def main():

    wordlist = raw_input("Enter a few words and I will find the longest: ").split(' ')
    word, length = find_longest_word(wordlist)
    print(word,"is the longest word that you have listed.")

 main()

Answer 3

Python 缩进敏感！ Python期望:之后的代码块。定义的结束由比当前缩进更小的缩进确定。

与C系列不同，Python没有{}来确定块的开始或结束位置。

您的代码应如下所示：

def find_longest_word(a):
    length = len(a[0])
    word = a[0]
    for i in wordlist:
         if len(i) > length:
              word = (i)
              length = len(i)

    return word, length

def main(): #EXPECTS INDENTATION
    #CODE INSIDE THE INDENTED CODE BLOCK WILL BE EXECUTED
    #ONLY IF FUNCTION main() IS CALLED
    wordlist = input("Enter a few words and I will find the longest: ").split()
    word, length = find_longest_word(wordlist)
    print (word,"is the longest word that you have listed.")

#END OF INDENTATION MARKS THE END OF A CODE BLOCK 
#THIS MEANS main() WILL GET CALLED EVERYTIME YOU 
#START THIS PROGRAM IN IDLE
main()

除此之外，您的代码中还会出现一些逻辑错误，这些错误也会导致错误。

错误：预期缩进块

3 个答案: