README_EN.md

468. Validate IP Address

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Description

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 <= xi <= 255 and xi 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 "[email protected]" are invalid IPv4 addresses.

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

• 1 <= xi.length <= 4
• xi 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 xi.

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.

 

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 ':'.

Solutions

Python3

Java

TypeScript

function validIPAddress(queryIP: string): string {
    const isIPv4 = () => {
        const ss = queryIP.split('.');
        if (ss.length !== 4) {
            return false;
        }
        for (const s of ss) {
            const num = Number(s);
            if (num < 0 || num > 255 || num + '' !== s) {
                return false;
            }
        }
        return true;
    };
    const isIPv6 = () => {
        const ss = queryIP.split(':');
        if (ss.length !== 8) {
            return false;
        }
        for (const s of ss) {
            if (s.length === 0 || s.length > 4) {
                return false;
            }
            for (const c of s) {
                if (
                    (c >= '0' && c <= '9') ||
                    (c >= 'a' && c <= 'f') ||
                    (c >= 'A' && c <= 'F')
                ) {
                    continue;
                }
                return false;
            }
        }
        return true;
    };
    if (isIPv4()) {
        return 'IPv4';
    }
    if (isIPv6()) {
        return 'IPv6';
    }
    return 'Neither';
}

Rust

impl Solution {
    fn is_IPv4(s: &String) -> bool {
        let ss = s.split('.').collect::<Vec<&str>>();
        if ss.len() != 4 {
            return false;
        }
        for s in ss {
            match s.parse::<i32>() {
                Err(_) => return false,
                Ok(num) => {
                    if num < 0 || num > 255 || num.to_string() != s.to_string() {
                        return false;
                    }
                }
            }
        }
        true
    }


    fn is_IPv6(s: &String) -> bool {
        let ss = s.split(':').collect::<Vec<&str>>();
        if ss.len() != 8 {
            return false;
        }
        for s in ss {
            if s.len() == 0 || s.len() > 4 {
                return false;
            }
            for &c in s.as_bytes() {
                if c >= b'0' && c <= b'9' || c >= b'a' && c <= b'f' || c >= b'A' && c <= b'F' {
                    continue;
                }
                return false;
            }
        }
        true
    }


    pub fn valid_ip_address(query_ip: String) -> String {
        if Self::is_IPv4(&query_ip) {
            return String::from("IPv4");
        }
        if Self::is_IPv6(&query_ip) {
            return String::from("IPv6");
        }
        String::from("Neither")
    }
}

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