Start by clarifying requirements and edge cases, then outline a straightforward O(n) solution that processes each character individually. Emphasize modular arithmetic for wrapping and case preservation, and discuss potential optimizations or trade-offs.
Pro tip: Demonstrate attention to detail by handling negative shifts and large shift values using modulo, and mention that the solution is O(n) time and O(n) space for the output string (or O(1) extra space if modifying in place).
Ask about input constraints (e.g., shift range, string length, character set) and expected behavior for non-alphabetic characters, negative shifts, and large shifts.
Explain that you will iterate through each character, check if it's alphabetic, and if so, compute its new position using modular arithmetic while preserving case.
Describe how to normalize the shift (e.g., shift % 26) and apply it separately for uppercase and lowercase letters, wrapping around using modulo.
State that the solution is O(n) time and O(n) space for the output string (or O(1) extra space if modifying in place), and discuss potential optimizations like using a precomputed mapping.
Walk through a few test cases, including edge cases like empty string, all non-alphabetic characters, and shifts that wrap multiple times.
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