Python迭代地替换字符串中的空格[关闭]

Question

我试图在 python 中的每个可能位置一次用连字符替换一个空格。例如the man said hi 应该生成所有可能的连字符位置的列表，包括多个连字符：

the-man said hi
the man-said hi
the man said-hi 
the-man said-hi
the-man-said hi
the man-said-hi
the-man-said-hi

字符串的长度因空格数而异，因此不能仅修复 3 个空格。我一直在尝试使用 re.search 和 re.sub 在 while 循环中，但还没有找到一个好的方法。

Answer 1

使用itertools.product() 生成所有空格和破折号组合，然后将您的字符串与这些组合重新组合：

from itertools import product

def dashed_combos(inputstring):
    words = inputstring.split()
    for combo in product(' -', repeat=len(words) - 1):
        yield ''.join(w for pair in zip(words, combo + ('',)) for w in pair)

最后一行将单词与破折号和空格一起压缩（在末尾添加一个空字符串以组成对），然后将其展平并将它们连接成一个字符串。

演示：

>>> for combo in dashed_combos('the man said hi'):
...     print combo
... 
the man said hi
the man said-hi
the man-said hi
the man-said-hi
the-man said hi
the-man said-hi
the-man-said hi
the-man-said-hi

您始终可以使用itertools.islice() 跳过该循环的第一次迭代（只有空格）：

from itertools import product, islice

def dashed_combos(inputstring):
    words = inputstring.split()
    for combo in islice(product(' -', repeat=len(words) - 1), 1, None):
        yield ''.join(w for pair in zip(words, combo + ('',)) for w in pair)

所有这些都非常节省内存；您可以轻松处理数百个单词的输入，只要您不尝试将所有可能的组合一次存储在内存中。

略长的演示：

>>> for combo in islice(dashed_combos('the quick brown fox jumped over the lazy dog'), 10):
...     print combo
... 
the quick brown fox jumped over the lazy-dog
the quick brown fox jumped over the-lazy dog
the quick brown fox jumped over the-lazy-dog
the quick brown fox jumped over-the lazy dog
the quick brown fox jumped over-the lazy-dog
the quick brown fox jumped over-the-lazy dog
the quick brown fox jumped over-the-lazy-dog
the quick brown fox jumped-over the lazy dog
the quick brown fox jumped-over the lazy-dog
the quick brown fox jumped-over the-lazy dog
>>> for combo in islice(dashed_combos('the quick brown fox jumped over the lazy dog'), 200, 210):
...     print combo
... 
the-quick-brown fox jumped-over the lazy-dog
the-quick-brown fox jumped-over the-lazy dog
the-quick-brown fox jumped-over the-lazy-dog
the-quick-brown fox jumped-over-the lazy dog
the-quick-brown fox jumped-over-the lazy-dog
the-quick-brown fox jumped-over-the-lazy dog
the-quick-brown fox jumped-over-the-lazy-dog
the-quick-brown fox-jumped over the lazy dog
the-quick-brown fox-jumped over the lazy-dog
the-quick-brown fox-jumped over the-lazy dog