Validate IP Address

Problem Statement

Given a string queryIP, return "IPv4" if IP is a valid IPv4 address, "IPv6" if IP is a valid IPv6 address or "Neither" if IP is not a correct IP of any type.

A valid IPv4 address is an IP in the form "x1.x2.x3.x4" where 0 <= x_i <= 255 and x_i cannot contain leading zeros. For example, "192.168.1.1" and "192.168.1.0" are valid IPv4 addresses while "192.168.01.1", "192.168.1.00", and "192.168@1.1" are invalid IPv4 addresses.

A valid IPv6 address is an IP in the form "x1:x2:x3:x4:x5:x6:x7:x8" where:

• 1 <= x_i.length <= 4
• x_i is a hexadecimal string which may contain digits, lowercase English letter ('a' to 'f') and upper-case English letters ('A' to 'F').
• Leading zeros are allowed in x_i.

For example,

"2001:0db8:85a3:0000:0000:8a2e:0370:7334" and "2001:db8:85a3:0:0:8A2E:0370:7334" are valid IPv6 addresses, while "2001:0db8:85a3::8A2E:037j:7334" and "02001:0db8:85a3:0000:0000:8a2e:0370:7334" are invalid IPv6 addresses.

Leetcode Link

Example 1:

Input: queryIP = "172.16.254.1"
Output: "IPv4"
Explanation: This is a valid IPv4 address, return "IPv4".

Example 2:

Input: queryIP = "2001:0db8:85a3:0:0:8A2E:0370:7334"
Output: "IPv6"
Explanation: This is a valid IPv6 address, return "IPv6".

Example 3:

Input: queryIP = "256.256.256.256"
Output: "Neither"
Explanation: This is neither a IPv4 address nor a IPv6 address.

Constraints:

• queryIP consists only of English letters, digits and the characters '.' and ':'.

Code

Python Code

from collections import deque
class Solution:
    def validIPAddress(self, IP):

        def isIPv4(s):
            try: return str(int(s)) == s and 0 <= int(s) <= 255
            except: return False

        def isIPv6(s):
            try: return len(s) <= 4 and int(s, 16) >= 0
            except: return False

        if IP.count(".") == 3 and all(isIPv4(i) for i in IP.split(".")):
            return "IPv4"
        if IP.count(":") == 7 and all(isIPv6(i) for i in IP.split(":")):
            return "IPv6"
        return "Neither"