regex ip-address

const pattern = /^((25[0-5]|2[0-4]\d|1\d{2}|[1-9]\d|\d)\.){3}(25[0-5]|2[0-4]\d|1\d{2}|[1-9]\d|\d)$/;

// Test a string
console.log(pattern.test("192.168.1.1")); // true
console.log(pattern.test("256.0.0.1")); // false

// Match and extract
const result = "192.168.1.1".match(pattern);

import re

pattern = r"^((25[0-5]|2[0-4]\d|1\d{2}|[1-9]\d|\d)\.){3}(25[0-5]|2[0-4]\d|1\d{2}|[1-9]\d|\d)$"

# Test a string
if re.fullmatch(pattern, "192.168.1.1"):
    print("Valid")

# Find all matches in text
matches = re.findall(pattern, text)

import java.util.regex.*;

String pattern = "^((25[0-5]|2[0-4]\\d|1\\d{2}|[1-9]\\d|\\d)\\.){3}(25[0-5]|2[0-4]\\d|1\\d{2}|[1-9]\\d|\\d)$";
Pattern p = Pattern.compile(pattern);

Matcher m = p.matcher("192.168.1.1");
boolean isValid = m.matches(); // true

// Find occurrences
Matcher finder = p.matcher(inputText);
while (finder.find()) {
    System.out.println(finder.group());
}