Question

I’m looking for a regular expression that would match 1 to n occurrences of numbers and only one occurrence of an arithmetic operator (only + or – are allowed)

For example, it should match -123 or 123- or +123 or 123+

This is what I have so far

import re

number = "-123" 

if re.findall(r"[0-9]+[+|-]?", number): 
    return True
else:
    return False

Answer 1

try something like this:

In [55]: strs
Out[55]: '+123 abc 123 -123 123- 123+ 14 foo bar'

   #you need to escape '+'and '-' In order to search them   

In [56]: re.findall(r"\d+[\+|\-]{1}|[\-|\+]{1}\d+",strs)
Out[56]: ['+123', '-123', '123-', '123+']