CodingMediumcod-g636

Subject MathLevel Mid–Senior~18 minCommon in Algorithms & data structures interviewsIndustries Software development, IT services

Question

Convert a positive integer column number to its Excel/spreadsheet column title (1 -> 'A', 26 -> 'Z', 27 -> 'AA', 28 -> 'AB', 702 -> 'ZZ', 703 -> 'AAA'). This is bijective base-26 (there is no zero digit). Constraints: 1 <= n <= 2^31 - 1. Return the title string.

Implement

excel_column_title(n: int) → str

Examples

in[28]out"AB"

What a strong answer looks like

State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.

Learn the concepts

Vibe coding: describe the solution in plain language (or narrate it) and the coach grades your approach. Generating runnable code from your description is coming next.

Run or narrate your approach, then ask the coach.