編寫一個(gè)復(fù)數(shù)類，可以進(jìn)行復(fù)數(shù)加法和減法運(yùn)算。編寫一個(gè)包含main方法的類（應(yīng)用程序）測(cè)試該復(fù)數(shù)類。要求該復(fù)數(shù)類至少包含一個(gè)無參的構(gòu)造方法和一個(gè)帶參的構(gòu)造方法；數(shù)據(jù)成員包括復(fù)數(shù)的實(shí)部和虛部，為double類型；包括兩個(gè)方法，分別實(shí)現(xiàn)復(fù)數(shù)的加法和減法運(yùn)算。代碼import java.util.Scanner;public class ComplexNum { double RealNum; double ImagNum; public ComplexNum() { Scanner input=new Scanner(System.in); RealNum=input.nextDouble(); ImagNum=input.nextDouble(); //ComplexNum(RealNum,ImagNum); } public ComplexNum(double RealNum,double ImagNum) { this.RealNum=RealNum; this.ImagNum=ImagNum;? ? } public ComplexNum add(ComplexNum b) { double RealNum1=this.RealNum; ? ? double ImagNum1=this.ImagNum; ? ? double LastReal=RealNum+RealNum1; ? ? double LastImag=ImagNum+ImagNum1; ? ? ComplexNum result=new ComplexNum(LastReal,LastImag); ? ? return result; } public ComplexNum mul(ComplexNum b) { double RealNum1=this.RealNum; ? ? double ImagNum1=this.ImagNum; ? ? double LastReal=RealNum-RealNum1; ? ? double LastImag=ImagNum-ImagNum1; ? ? ComplexNum result=new ComplexNum(LastReal,LastImag); ? ? return result; } public void printf() { if(ImagNum>0) { System.out.println(ImagNum+"+"+"j"+RealNum); } else if(ImagNum<0) { System.out.println(ImagNum+"-"+"j"+RealNum); } else { System.out.println(RealNum); } } public static void main(String[] args) { System.out.println("請(qǐng)輸入第一個(gè)復(fù)數(shù)的實(shí)部和虛部"); ComplexNum a=new ComplexNum(); System.out.println("請(qǐng)輸入第二個(gè)復(fù)數(shù)的實(shí)部和虛部"); ComplexNum b=new ComplexNum();? ? ? ?? ComplexNum add=a.add(b); ComplexNum mul=a.mul(b); add.printf(); mul.printf(); }}