Parse Nested ArrayList-like String to Nested List

Problem: Parse a Nested ArrayList-like String You are given a string s representing an ArrayList<String>. The list may be nested. Parse it into an in-memory nested list structure (e.g., a Python list whose elements are either strings or sub-lists). Input Format (guaranteed valid) Lists are denoted by square brackets: [ and ]. Elements are separated by commas ,. Each element is either: a double-quoted string, e.g. "abc", or another list (nested). String contents contain only letters and digits (no quotes/commas/brackets/backslashes), so no escaping needs to be handled. Whitespace (spaces/newlines/tabs) may appear and should be ignored. Output Print the parsed nested list in a canonical form for judging: Use JSON-style printing (same as Python json.dumps): strings use double quotes lists use square brackets no strict requirement on spaces Constraints 1 <= len(s) <= 2 * 10^5 Nesting depth <= 10^4 Examples Input: ["a","b",["c","d"],"e"] Output: ["a","b",["c","d"],"e"] Input: ["x",[]] Output: ["x",[]] Requirement Solve in O(n) time; using a stack is recommended. Example Input ["a","b",["c","d"],"e"] Output ["a","b",["c","d"],"e"]