Short Problem Definition:

Consider a string, s, consisting only of the letters a and b. We say that string s is balanced if both of the following conditions are satisfied:

1. s has the same number of occurrences of a and b.
2. In each prefix of s, the number of occurrences of a and b differ by at most 1.

Your task is to write a regular expression accepting only balanced strings.

Link

Balanced Strings

Execution:

Substrings can differ by at most 1 which means that the string must consist of either “ab” or “ba”. Write a regex as such.

Solution:

Regex_Pattern = r"^((ab)|(ba))*$"	# Do not delete 'r'.