class XS    {        private double RP;         //实部        private double IP;         //虚部        public double getRP        {            get { return RP; }        }        public double getIP        {            get { return IP; }        }        public XS()  //构造函数        {            RP = IP = 0;        }        public XS(double RP, double IP)//构造函数重载        {            this.RP = RP;            this.IP = IP;        }        //加号+重载        public static XS operator +(XS c1, XS c2)        {            XS c = new XS(c1.RP + c2.RP, c1.IP + c2.IP);            return c;        }        //对取反符号-重载(一元运算符重载)        public static XS operator -(XS c)        {            XS c2 = new XS(-c.RP, -c.IP);            return c2;        }        //对减号-重载（二元运算符重载）        public static XS operator -(XS c1, XS c2)        {            XS c = new XS(c1.RP - c2.RP, c1.IP - c2.IP);            return c;        }        //实现隐式类型转换（从 string 到 XS）        public static implicit operator XS(string s)        {            s = s.Trim().TrimEnd(‘i‘);            s = s.Trim().TrimEnd(‘*‘);            string[] digits = s.Split(‘+‘, ‘-‘);            XS c;            c = new XS(Convert.ToDouble(digits[0]), Convert.ToDouble(digits[1]));            return c;        }        //输出虚数        public void putOut()        {            Console.WriteLine("{0} + {1}*i", RP, IP);        }    }static void Main(string[] args)        {            //调用不带参数的构造函数创建虚数对象c1            XS c1 = new XS();            //调用带参数的构造函数创建虚数对象c2            XS c2 = new XS(1, 2);            Console.Write("c1 = "); c1.putOut();            Console.Write("c2 = "); c2.putOut();            XS c3;            c3 = "100+200*i";                 // 通过隐式转换对c3赋值            Console.Write("c3 = "); c3.putOut();            XS c4;            c4 = -c2 - c1 + c3;                //对对象进行加减运算            Console.Write("c4 = "); c4.putOut();            Console.ReadKey();        }