using google

m2.cs

class Program
    {
        private const string Xpath = "//*[@id=\"cwos\"]";

        static void Main(string[] args)
        {
            var val = string.Empty;

            var num1 = Convert.ToInt32(args[0]);
            var num2 = Convert.ToInt32(args[1]);

            var task = Task.Run(async () =>
            {
                using (var client = new HttpClient())
                {
                    var url = "http://www.google.co.uk/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=" + num1 + "*" + num2;
                    var responseString = await client.GetStringAsync(url);
                    var doc = new HtmlDocument();
                    doc.LoadHtml(responseString);
                    var node = doc.DocumentNode.SelectNodes(Xpath)[0];
                    val = node.Attributes["value"].Value;
                }
            });

            Task.WaitAll(new[] { task });
            Console.WriteLine(val);
            Console.ReadLine();
        }
    }