Java复数类实现加减运算

import java.util.Scanner;

class Complex { private double realPart; private double imaginaryPart;

public Complex() {
    this.realPart = 0;
    this.imaginaryPart = 0;
}

public Complex(double realPart, double imaginaryPart) {
    this.realPart = realPart;
    this.imaginaryPart = imaginaryPart;
}

public double getRealPart() {
    return realPart;
}

public void setRealPart(double realPart) {
    this.realPart = realPart;
}

public double getImaginaryPart() {
    return imaginaryPart;
}

public void setImaginaryPart(double imaginaryPart) {
    this.imaginaryPart = imaginaryPart;
}

public Complex add(Complex other) {
    double realSum = this.realPart + other.realPart;
    double imaginarySum = this.imaginaryPart + other.imaginaryPart;
    return new Complex(realSum, imaginarySum);
}

public Complex sub(Complex other) {
    double realDiff = this.realPart - other.realPart;
    double imaginaryDiff = this.imaginaryPart - other.imaginaryPart;
    return new Complex(realDiff, imaginaryDiff);
}

@Override
public String toString() {
    return realPart + "+" + imaginaryPart + "i";
}

}

public class Main { public static void main(String[] args) { Complex a = new Complex(); Complex b = new Complex(); Scanner in = new Scanner(System.in); a.setRealPart(in.nextDouble()); a.setImaginaryPart(in.nextDouble()); b.setRealPart(in.nextDouble()); b.setImaginaryPart(in.nextDouble()); System.out.println(a); System.out.println(b); System.out.println(a.add(b)); System.out.println(a.sub(b)); } }