Python 从字符串中删除多个字符序列

如果我有这样的字符串：

my_string = 'this is is is is a string'

如何删除多个

is

s，以便只显示一个

此字符串中可以包含任意数量的

is

，例如

my_string = 'this is is a string'
other_string = 'this is is is is is is is is a string'

---

我想一个正则表达式解决方案是可能的，但是我不知道该怎么做。谢谢。

如果您想一个接一个地删除所有副本，您可以尝试

l = my_string.split()
tmp = [l[0]]
for word in l:
    if word != tmp[-1]:
        tmp.append(word)
s = ''
for word in tmp:
    s += word + ' '
my_string = s

当然，如果您希望它比这更智能，那么它将更加复杂。

对于OneLiner：

>>> import itertools
>>> my_string = 'this is is a string'
>>> " ".join([k for k, g in itertools.groupby(my_string.split())])
'this is a string'

你可以用

我的做法如下：

my_string = 'this is is a string'
other_string = 'this is is is is is is is is a string'
def getStr(s):
    res = []
    [res.append(i) for i in s.split() if i not in res]
    return ' '.join(res)

print getStr(my_string)
print getStr(other_string)

输出：

this is a string
this is a string

更新正则表达式攻击它的方法：

import re
print ' '.join(re.findall(r'(?:^|)(\w+)(?:\s+\1)*', other_string))

Regex拯救我们！ Python代码 演示

---

请参阅演示以及上的

统计“is”字符串的出现次数，并在计数器>1@MohitSharma肯定有更有效的解决方案吗？您只想删除

is

或任何重复出现的情况吗？像

'this is a string'

到

'this a string'

@PSidhu一样，大多数时候你都应该把你的attemptRelated:.你的非正则表达式方法将删除字符串中任何后续出现的单词：

getStr（'this string is string'）

-->this string is a'。虽然问题还不清楚，但我认为这可能不是OP的想法。你是对的。这对OP的问题有好处。我认为regex方法更可靠。

import re
print ' '.join(re.findall(r'(?:^|)(\w+)(?:\s+\1)*', other_string))

((\b\w+\b)\s*\2\s*)+
# capturing group
# inner capturing group
# ... consisting of a word boundary, at least ONE word character and another boundary
# followed by whitespaces
# and the formerly captured group (aka the inner group)
# the whole pattern needs to be present at least once, but can be there
# multiple times

import re

string = """
this is is is is is is is is a string
and here is another another another another example
"""
rx = r'((\b\w+\b)\s*\2\s*)+'

string = re.sub(rx, r'\2 ', string)
print string
# this is a string
# and here is another example