public static string ReverseString(string inputString){ char[] inputCharArray = inputString.ToCharArray();char[] reverseCharArray = new char[inputCharArray.Length];inputCharArray.CopyTo(reverseCharArray, 0);Array.Reverse(reverseCharArray);for(int i= 0; i< inputCharArray.Length; i ){if(!char.IsLetterOrDigit(reverseCharArray[i])){reverseCharArray[i] = inputCharArray[i];}}return new string(reverseCharArray);}