P1103

编程实现两个复数的运算。设有两个复数 和 ，则他们的运算公式为：

　　要求：（1）定义一个结构体类型来描述复数。
　　（2）复数之间的加法、减法、乘法和除法分别用不用的函数来实现。
　　（3）必须使用结构体指针的方法把函数的计算结果返回。
　　说明：用户输入：运算符号(+,-,*,/) a b c d.
　　输出：a+bi，输出时不管a,b是小于0或等于0都按该格式输出，输出时a,b都保留两位。

输入：
　　- 2.5 3.6 1.5 4.9
输出：
　　1.00+-1.30i

import java.util.*;

public class Main {
    private Scanner scanner;
    public static void main(String[] args) {
        new Main();
    }

    private Main(){
        scanner = new Scanner(System.in);
        solve();

    }

    private void solve(){
        char op = scanner.next().charAt(0);
        double a = scanner.nextDouble();
        double b = scanner.nextDouble();
        double c = scanner.nextDouble();
        double d = scanner.nextDouble();

        Complex complex = new Complex(a,b);
        if(op == '+'){
            complex.add(new Complex(c,d));
        }
        else if(op == '-'){
            complex.sub(new Complex(c,d));
        }
        else if(op == '*'){
            complex.mul(new Complex(c,d));
        }
        else if (op == '/'){
            complex.div(new Complex(c,d));
        }

        complex.print();
    }



}

class Complex{
    private double a;
    private double b;

    public Complex(double a,double b){
        this.a = a;
        this.b = b;
    }

    public void add(Complex complex){
        a += complex.a;
        b += complex.b;
    }

    public void sub(Complex complex){
        a -= complex.a;
        b -= complex.b;
    }

    public void mul(Complex complex){
        double c = complex.a;
        double d = complex.b;
        double temp = a;
        a = a*c-b*d;
        b = temp*d+b*c;
    }

    public void div(Complex complex){
        double c = complex.a;
        double d = complex.b;
        double temp = a;
        a = (a*c+b*d)/(c*c+d*d);
        b = (b*c-temp*d)/(c*c+d*d);
    }

    public void print(){
        System.out.printf("%.2f",a);
        System.out.print("+");
        System.out.printf("%.2f",b);
        System.out.println("i");
    }
}