Checks whether a subreddit already exists or not.

RedditChecker.cs

using System.Globalization;
using System.Text;

class Program
{
    static async Task Main()
    {
        var villes = new List<string>
        {
            "Moskva", "London", "Berlin", "Madrid", "Roma", "Paris", "București", "Wien",
            "Hamburg", "Budapest", "Warszawa", "Barcelona", "Milano", "Praha", "Sofia", "Bruxelles",
            "Birmingham", "Köln", "Napoli", "Stockholm", "Manchester", "Amsterdam", "Lisboa", "København",
            "Dublin", "Helsinki", "Lyon", "València", "München", "Frankfurt", "Stuttgart", "Düsseldorf",
            "Dortmund", "Essen", "Leipzig", "Hannover", "Nürnberg", "Dresden", "Bochum", "Wuppertal"
        };

        using var client = new HttpClient();

        client.DefaultRequestHeaders.Clear();
        client.DefaultRequestHeaders.Add("User-Agent",
            "Mozilla/5.0 (iPhone; CPU iPhone OS 9_3_5 like Mac OS X) AppleWebKit/601.1.46 (KHTML, like Gecko) Version/9.0 Mobile/13G36 Safari/601.1");
        client.DefaultRequestHeaders.Add("Accept", "text/html");

        foreach (var ville in villes)
        {
            var subreddit = RemoveAccents(ville.Replace(" ", "").Replace("-", "").Replace("&", ""));
            var url = $"https://www.reddit.com/r/{subreddit}/";

            try
            {
                var response = await client.GetAsync(url);
                var html = await response.Content.ReadAsStringAsync();

                bool notFound = html.Contains("Community not found");
                if (notFound)
                {
                    Console.ForegroundColor = ConsoleColor.Green;
                    Console.WriteLine($"{ville}> Pas de subreddit");
                }
                else
                {
                    Console.ForegroundColor = ConsoleColor.Red;
                    Console.WriteLine($"{ville}> Subreddit existe");
                }

                Console.ResetColor();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"{ville}> Erreur ({ex.Message})");
            }

            await Task.Delay(1000);
        }
    }

    public static string RemoveAccents(string text)
    {
        var normalizedString = text.Normalize(NormalizationForm.FormD);
        var stringBuilder = new StringBuilder();

        foreach (var c in normalizedString)
        {
            var unicodeCategory = CharUnicodeInfo.GetUnicodeCategory(c);
            if (unicodeCategory != UnicodeCategory.NonSpacingMark)
            {
                stringBuilder.Append(c);
            }
        }

        return stringBuilder.ToString().Normalize(NormalizationForm.FormC);
    }
}