Distinct tile sequences
Given a string `tiles` of uppercase letters (possibly with duplicates), return the number of distinct non-empty sequences you can form using the tiles, where each tile may be used at most once. For example with tiles `AAB`, sequences include `A`, `B`, `AA`, `AB`, `BA`, `AAB`, `ABA`, `BAA`. The string has length 1..10.
Implement
num_tile_possibilities(tiles: str) → intExamples
in
["AAB"]out8What 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 25 min
solution.py
InputExpectedGot
["AAB"]8not run yetsample