Minimum Character Replacements So No Two Adjacent Characters Are Equal

Company: Headlands

Role: Data Scientist

Category: Coding & Algorithms

Difficulty: medium

Interview Round: Online Assessment

Overview: Given a string of lowercase letters, find the minimum number of single-position replacements needed so that no two adjacent characters are equal. It tests turning an adjacency constraint into an exact minimum count, justifying why fewer operations cannot work, and handling edge cases in an efficient solution.

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