题解 | #验证IP地址#

class Solution:
    def solve(self, IP: str) -> str:
        def is_ipv4(ip):
            parts = ip.split(".")
            if len(parts) != 4:
                return False
            for part in parts:
                if (
                    not part.isdigit()
                    or not 0 <= int(part) <= 255
                    or (len(part) > 1 and part[0] == "0")
                ):
                    return False
            return True

        def is_ipv6(ip):
            parts = ip.split(":")
            if len(parts) != 8:
                return False
            for part in parts:
                if not (
                    1 <= len(part) <= 4
                    and all([c in "0123456789abcdefABCDEF" for c in part])
                ):
                    return False
            return True

        if is_ipv4(IP):
            return "IPv4"
        elif is_ipv6(IP):
            return "IPv6"
        else:
            return "Neither"