Counting Binary Substrings (Backend)

Problem Overview

• Count substrings in a binary string where 0s and 1s form consecutive groups and the counts of 0s and 1s are equal.
• Input: binary string s (length 5 to 5×10^5, only '0' and '1'); Output: integer count of valid substrings.
• Domain: backend string processing and binary data validation in streams.
• This coding interview problem is an interview question from Canva interviews (Backend).
• Complete counting(s) to return the total number of matching substrings.