Question

def remove_duplicates(strng):
    """
    Returns a string which is the same as the argument except only the
    first occurrence of each letter is present.  Upper and lower case
    letters are treated as different.  Only duplicate letters are removed,
    other characters such as spaces or numbers are not changed. 

    >>> remove_duplicates('apple')
    'aple'
    >>> remove_duplicates('Mississippi')
    'Misp'
    >>> remove_duplicates('The quick brown fox jumps over the lazy dog')
    'The quick brown fx jmps v t lazy dg'
    >>> remove_duplicates('121 balloons 2 u')
    '121 balons 2 u'
    """
    s = strng.split()
    return strng.replace(s[0],"")

编写一个函数来摆脱重复的字母，但到目前为止已经玩了一个小时而且无法得到任何东西。感谢帮助，谢谢。

Answer 1

不是最有效，但最直接的方式是：

>>> s = 'The quick brown fox jumps over the lazy dog'
>>> import string
>>> n = ''
>>> for i in s:
        if i not in string.ascii_letters:
            n += i
        elif i not in n:
            n += i


>>> n
'The quick brown fx jmps v t lazy dg'

Answer 2

使用列表理解：

>>> from string import whitespace, digits
>>> s = 'The quick brown fox jumps over the lazy dog'
>>> ''.join([c for i, c in enumerate(s) if c in whitespace+digits \
                                                      or not c in s[:i]])

Answer 3

试试这个......

def remove_duplicates(s):
    result = ""
    dic = {}
    for i in s:
        if i not in dic:
            result+=i
            if ord(i.lower()) >= ord('a') and ord(i.lower()) <= ord('z'):
                dic[i] = 1
    return result

Python - 从字符串中删除重复项

3 个答案: