How to get all overlapping matches in python regex that may start at the same location in a string?

Question

How do I get all possible overlapping matches in a string in Python with multiple starting and ending points.

I\'ve tried using regex module, instead of default re m

Answer 1

Regex are not the proper tool here, I would recommend:

• Identify all the indexes of the first letter in the input string
• Identify all the indexes of the second letter in the input string
• Build all the substrings based on those indexes

code:

def find(str, ch):
    for i, ltr in enumerate(str):
        if ltr == ch:
            yield i

s = "axaybzb"
startChar = 'a'
endChar = 'b'

startCharList = list(find(s,startChar))
endCharList = list(find(s,endChar))

output = []
for u in startCharList:
    for v in endCharList:
           if u <= v:
               output.append(s[u:v+1])
print(output)

output:

$ python substring.py 
['axayb', 'axaybzb', 'ayb', 'aybzb']