public static double CompareStrings(string str1, string str2)
        {
            List <string> list1 = SimilarityUtils.WordLetterPairs(str1.ToUpper());
            List <string> list2 = SimilarityUtils.WordLetterPairs(str2.ToUpper());
            int           num1  = 0;
            int           num2  = list1.Count + list2.Count;

            for (int index1 = 0; index1 < list1.Count; ++index1)
            {
                for (int index2 = 0; index2 < list2.Count; ++index2)
                {
                    if (list1[index1] == list2[index2])
                    {
                        ++num1;
                        list2.RemoveAt(index2);
                        break;
                    }
                }
            }
            return(2.0 * (double)num1 / (double)num2);
        }