string s1="hello";
            string s2="world";
            long L = (((long)s1.GetHashCode()) << 32) + s2.GetHashCode();
            //L= -1406257598958874302

public unsafe static int Get_Hash_Code( string s)
        {
            List<char> cc = new List<char>();
            for (int i = 0; i < s.Length; i++) cc.Add(s[i]);
            fixed (char* str = &(cc.ToArray())[0])
            {
                int num3;
                char* chPtr = str;
                int num = 0x1505;
                int num2 = num;
                for (char* chPtr2 = chPtr; (num3 = chPtr2[0]) != '\0'; chPtr2 += 2)
                {
                    num = ((num << 5) + num) ^ num3;
                    num3 = chPtr2[1];
                    if (num3 == 0) break;
                    num2 = ((num2 << 5) + num2) ^ num3;
                }
                return (num + (num2 * 0x5d588b65));
            }
        }