My first instinct was to just try all 26 rotations for each string and use that as a key, which works but felt clunky.
Normalize each string to a canonical form by shifting it so that its first character becomes 'a', then group strings by this canonical key using a hash map. This reduces the problem to finding a consistent representative for each equivalence class under Caesar shifts.
Pro tip: Clarify whether the shift is applied uniformly to all characters and whether the alphabet is circular; also discuss handling empty strings and strings with non-alphabetic characters, as these edge cases often trip candidates.
Confirm that two strings are equivalent if one can be obtained from the other by shifting every character by the same amount (mod 26). Ask about alphabet size, character set, and empty strings.
For each string, compute the shift needed to make its first character 'a' (or any fixed character), then apply that shift to all characters to get a normalized string. This normalized string uniquely identifies the equivalence class.
Use a dictionary mapping the canonical string to a list of original strings. Iterate through the input list, compute the canonical form, and append the original string to the corresponding list.
Time complexity is O(N * L) where N is number of strings and L is average length. Space is O(N * L). Discuss handling of empty strings, strings of different lengths, and non-alphabetic characters.
Walk through examples like ['abc', 'bcd', 'xyz'] to ensure they group correctly. Consider edge cases such as empty strings, single-character strings, and strings with uppercase letters.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.