Python - 如何仅在字符串中连续删除重复项？

Question

对于一个字符串,例如'12233322155552',通过删除重复项,我可以得到'1235'.

但我想保留的是'1232152',只删除连续的重复项.

Answer 1

微软/亚马逊求职面试的问题类型:这是伪代码,实际代码留作练习.

for each char in the string do:
   if the current char is equal to the next char:
      delete next char
   else
     continue

return string

作为更高级别,尝试(实际上不是实现):

for s in string:
  if s == s+1:  ## check until the end of the string
     delete s+1

Answer 2

你可以使用itertools,这里是一个班轮

>>> s = '12233322155552'
>>> ''.join(i for i, _ in itertools.groupby(s))
'1232152'

Answer 3

import re

# Only repeated numbers
answer = re.sub(r'(\d)\1+', r'\1', '12233322155552')

# Any repeated character
answer = re.sub(r'(.)\1+', r'\1', '12233322155552')

Answer 4

提示:itertools模块非常有用.一个函数,特别是itertools.groupby,可能在这里非常方便:

itertools.groupby(iterable [,key])

创建一个从迭代中返回连续键和组的迭代器.关键是计算每个元素的键值的函数.如果未指定或为None,则键默认为标识函数并返回元素不变.通常,可迭代需要已经在相同的键函数上排序.

因此,由于字符串是可迭代的,您可以做的是:

use groupby to collect neighbouring elements
extract the keys from the iterator returned by groupby
join the keys together

这一切都可以在一条简洁的线上完成..