Count Num Ways

Problem Overview

• Count how many length-k substring reversals in string s produce a lexicographically smaller string.
• Input: string s and integer k; output: an integer count under constraints 2 <= |s| <= 1e6 and 1 <= k <= min(|s|, 20).
• Set in a hashing context where the count can act as a seed derived from the original string.
• This Amazon interviews coding interview problem is a common interview question about string ordering and comparison.