C# AdBlocker

using System;
using System.IO;
using System.Text.RegularExpressions;

class AdBlocker
{
    private Regex adRegex;

    public AdBlocker()
    {
        // Load the list of ad domains from a file
        LoadAdDomains("ad_domains.txt");
    }

    public void LoadAdDomains(string filePath)
    {
        try
        {
            // Read the file containing ad domains
            string[] domains = File.ReadAllLines(filePath);

            // Create a regular expression pattern to match ad domains
            string pattern = string.Format(@"(^|\.)({0})$", string.Join("|", domains));

            // Compile the regular expression
            adRegex = new Regex(pattern, RegexOptions.Compiled | RegexOptions.IgnoreCase);
        }
        catch (Exception ex)
        {
            Console.WriteLine("Failed to load ad domains: " + ex.Message);
        }
    }

    public bool IsAd(string url)
    {
        // Check if the URL matches the ad domain pattern
        return adRegex.IsMatch(url);
    }
}

class Program
{
    static void Main()
    {
        // Create an instance of the AdBlocker
        AdBlocker adBlocker = new AdBlocker();

        // Test URLs
        string[] urls = {
            "https://www.example.com",
            "https://ads.example.com",
            "https://www.advertisement.com",
            "https://www.example.org"
        };

        // Check if each URL is an ad
        foreach (string url in urls)
        {
            bool isAd = adBlocker.IsAd(url);
            Console.WriteLine("{0}: {1}", url, isAd ? "Blocked" : "Allowed");
        }
    }
}