Excel column number
Given an Excel-style column title (a string of uppercase letters A-Z, e.g. 'A', 'Z', 'AA', 'AB', ... 'ZY'), return its corresponding 1-based column number. A=1, Z=26, AA=27, AB=28, and so on. The title has length 1 to 7. This is bijective base-26 (there is no zero digit).
Implement
excel_col_number(s: str) → intExamples
in
["A"]out1What 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.
0:00 of about 15 min
solution.py
InputExpectedGot
["A"]1not run yetsample