Question

468. Validate IP Address

中文文档

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 "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 <= 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

Solution 1

class Solution:
  def validIPAddress(self, IP: str) -> str:
    if "." in IP:
      segments = IP.split(".")
      if len(segments) != 4:
        return "Neither"
      for segment in segments:
        if (
          not segment.isdigit()
          or not 0 <= int(segment) <= 255
          or (segment[0] == "0" and len(segment) > 1)
        ):
          return "Neither"
      return "IPv4"
    elif ":" in IP:
      segments = IP.split(":")
      if len(segments) != 8:
        return "Neither"
      for segment in segments:
        if (
          not segment
          or len(segment) > 4
          or not all(c in string.hexdigits for c in segment)
        ):
          return "Neither"
      return "IPv6"
    return "Neither"

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';
}

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")
  }
}