public static int SundaySearch(string text, string pattern)
        {
            int i = 0;
            int j = 0;
            int m = pattern.Length ;

            int matchPosition = i;

            while (i < text.Length && j < pattern.Length)
            {
                if (text[i] == pattern[j])
                {
                    i++;
                    j++;
                }
                else
                {
                    if(m==text.Length-1)break;

                    int k = pattern.Length - 1;

                    while (k >= 0 && text[m ] != pattern[k])
                    {
                        k--;
                    }

                    int gap = pattern.Length - k;
                    i += gap;
                    m = i + pattern.Length;
                    if (m > text.Length) m = text.Length - 1;
                    matchPosition = i;
                    j = 0;
                }
            }

            if (i <= text.Length)
            {
                return matchPosition;
            }

            return -1;
        }

public static void PerformanceTest()
        {
            StreamReader reader = new StreamReader("D://LogConfiguration.xml", Encoding.ASCII);
            string context = reader.ReadToEnd();
            string pattern = "xxxx";
            int count = 1000*10;

            Stopwatch watch=new Stopwatch();

            //watch.Start();
            //for (int i = 0; i < count; i++)
            //{
            //    int pos= Sunday.GetPositionFirst(context, pattern, true);
            //}
            //watch.Stop();
            //Console.WriteLine(watch.ElapsedMilliseconds);

            watch.Reset();
            watch.Start();
            for (int i = 0; i < count; i++)
            {
                int pos = context.IndexOf(pattern);
            }
            watch.Stop();
            Console.WriteLine(watch.ElapsedMilliseconds);

            watch.Reset();
            watch.Start();
            for (int i = 0; i < count; i++)
            {
                int pos = Sunday.SundaySearch(context, pattern);
            }
            watch.Stop();
            Console.WriteLine(watch.ElapsedMilliseconds);
        }