昨天面试了微软北京的组，Coding问了一道判断IP是否合法的问题，然鹅当时脑子打铁，写的完全惨不忍睹，今天早上起床吓得我赶紧重新写了一遍。
class Solution(object): def isIPv4(self, s): try: return str(int(s)) == s and 0 <= int(s) <= 255 except: return False def isIPv6(self, s): if len(s) > 4: return False try: return int(s, 16) >= 0 and s[0] != '-' except: return False def validIPAddress(self, IP): """ :type IP: str :rtype: str """ if IP.count(".") == 3 and all(self.isIPv4(i) for i in IP.split(".")): return "IPv4" if IP.count(":") == 7 and all(self.isIPv6(i) for i in IP.split(":")): return "IPv6" return "Neither"