Question
Decode a string encoded with the rule k[encoded], meaning the bracketed substring is repeated k times; encodings can be nested. k is a positive integer (possibly multiple digits) and the bracketed content is itself a valid encoded string. For example "3[a2[c]]" decodes to "accaccacc" and "2[abc]3[cd]ef" decodes to "abcabccdcdcdef". The input is always well-formed and contains only lowercase letters, digits, and brackets. Return the decoded string.
decode_string(s: str) → str["3[a2[c]]"]out"accaccacc"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.
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.