REGEH - Jordan3900

            var input = Console.ReadLine();
            var pattern = @"\[[A-Z&a-z]+<([0-9]+)REGEH([0-9]+)>[A-Z&a-z]+\]";
            var regex = Regex.Matches(input, pattern);
            var nums = new List<int>();

            foreach (Match match in regex)
            {
                nums.Add(int.Parse(match.Groups[1].Value));
                nums.Add(int.Parse(match.Groups[2].Value));
            }

            int numSum = 0;
            string result = string.Empty;
            for (int i = 0; i < nums.Count; i++)
            {
                numSum += nums[i];
                numSum %= input.Length;
                result += input[numSum];
            }

            Console.WriteLine(result);