复数类Complex的Java实现(数据结构 例 1-4)

/*实现一个复数类的加减乘除运算*/import java.util.*;public class Complex {private double a,b;//复数的实部和虚部//private final double delta=1e-20;public Complex(double a,double b){this.a=a;this.b=b;}public void Change(double a,double b){this.a=a;this.b=b;}public String toString(){if(b>0.0){if(a==0.0)return b+"*i";elsereturn a+"+"+b+"*i";}else if(b<0.0){if(a==0.0)return b+"*i";elsereturn a+""+b+"*i";//注意}elsereturn a+"";//要加"",这样就可以返回一个String类型的值了}public Complex add(Complex Z){double aa=this.a+Z.a;double bb=this.b+Z.b;return new Complex(aa,bb);}public Complex subtract(Complex Z){double aa=this.a-Z.a;double bb=this.b-Z.b;return new Complex(aa,bb);}public Complex multiply(Complex Z){double aa=this.a*Z.a-this.b*Z.b;double bb=this.b*Z.a+this.a*Z.b;return new Complex(aa,bb);}public Complex divide(Complex Z){Z.Change(Z.a, -Z.b);Complex ZZ=this.multiply(Z);//System.out.println(ZZ.a+" "+ZZ.b);ZZ.a/=(Z.a*Z.a+Z.b*Z.b);ZZ.b/=(Z.a*Z.a+Z.b*Z.b);return ZZ;}public static void main(String args[]){Scanner cin=new Scanner(System.in);Complex Z1,Z2,Z3;Z1=new Complex(0,0);Z2=new Complex(0,0);Z3=Z1.add(Z2);//java中double会保留一位小数，但如果有超过一位的小数，那输出全部小数，C默认固定保留六位小数System.out.println(Z1+"\n"+Z2+"\n"+Z3);double a,b,c,d;while(cin.hasNext()){a=cin.nextDouble();b=cin.nextDouble();Z1.Change(a, b);c=cin.nextDouble();d=cin.nextDouble();Z2.Change(c, d);Z3=Z1.add(Z2);System.out.println(Z3);Z3=Z1.subtract(Z2);System.out.println(Z3);Z3=Z1.multiply(Z2);System.out.println(Z3);Z3=Z1.divide(Z2);System.out.println(Z3);}}}