Valid IPv4 addresses
Given a string of only digits, return all possible valid IPv4 addresses that can be formed by inserting three dots, in ascending lexicographic order. Each of the four octets must be 0-255 with no leading zeros (a single '0' is allowed). 0 <= len(s) <= 12. Example: '25525511135' -> ['255.255.11.135','255.255.111.35'].
Implement
restore_ip_addresses(s: str) → list[str]Examples
in
["25525511135"]out["255.255.11.135","255.255.111.35"]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.
0:00 of about 22 min
solution.py
InputExpectedGot
["25525511135"]["255.255.11.135","255.255.111.35"]not run yetsample