How Python with regular expressions, the first to obtain a string to repeat the English letters

The existing scheme is:
Object according to the re module inside of a regular expression search method can specify the start and stop position features, design each found a result on a unit, and then compare all find the result of the last index the smallest is the answer of a group,
Is very troublesome, simple and direct method


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# 2:
# to find out all of the repeating group, adopting the span () [1] the smallest group
The import re, sys
Pa=re.com running (r "(? I) ([a zA - Z]). * \ 1 ")

# using a regular expression objects can specify additional characteristics of the starting and ending position
# each find a result go forward by one unit
Start=0
Result=pa. Search (random_str, start)
Result_list=[]
# if there is no result directly print (1, 1)
If the result is None:
Print (" no repeated letters ")
Sys. Exit (0)

While the result:
Start=result. The pos + 1
# if there is repeated as a result, the continue directly
If len (result_list) & gt; 0 and the result. The span () [0]==result_list [len (result_list) - 1] [0] and result. The span () [1]==\
Result_list [len (result_list) - 1] [1] :
Result=pa. Search (random_str, start)
The continue
Result_list. Append (result)
Result=pa. Search (random_str, start)

# the last character of the plane, and find out the smallest a
Earliest_index=0
Lowest_value=https://bbs.csdn.net/topics/result_list [0]. Span () [1]
For I in range (1, len (result_list) :
If result_list [I] span () [1] Lowest_value=https://bbs.csdn.net/topics/result_list [I] span () [1]
Earliest_index=I
Print (" the first English letters to repeat: ", result_list [earliest_index] group () [0])

CodePudding user response:

Need regular??
For I in a:
If I in b:
Print (I)
The else:
B.a ppend (I)

CodePudding user response:

But if use regular expressions to how to write, but if the loop through is simple, the subject is to use regular expressions to...

CodePudding user response:

There is no matching target and matching rules, can only be in the form of a string operation to complete the task

CodePudding user response:

Not like this?
Re. The.findall (r "([a zA - Z]) \ 1", STR)

CodePudding user response:

It will appear an intermediate string not available, such as "acca", he is getting less than c of this group, it is to be able to query to a result, this in the middle of the content is passed, will ignore many things

CodePudding user response:

reference 5 floor Mlng reply:

it will appear an intermediate string not available, such as "acca", he is getting less than c of this group, it is to be able to query to a result, this in the middle of the content is passed, will ignore many

What are you going to achieve, for example, if somebody else answer over, you again to the exception, that is no way to solve,
The import re
X='acca'
Re. The.findall (r "([a zA - Z]) \ 1", x)
[' c ']