1、调试通过：（1）复数类。编写一个类实现复数的运算。要求至少实现复数相加、复数相减、复数相乘等功能。

在Java中创建一个复数类，用于支持复数的加法、减法和乘法操作，你可以按照以下步骤实现：

public class ComplexNumber {
    private double real; // 实部
    private double imaginary; // 虚部

    // 构造函数
    public ComplexNumber(double real, double imaginary) {
        this.real = real;
        this.imaginary = imaginary;
    }

    // 复数相加
    public ComplexNumber add(ComplexNumber other) {
        double newReal = this.real + other.real;
        double newImaginary = this.imaginary + other.imaginary;
        return new ComplexNumber(newReal, newImaginary);
    }

    // 复数相减
    public ComplexNumber subtract(ComplexNumber other) {
        double newReal = this.real - other.real;
        double newImaginary = this.imaginary - other.imaginary;
        return new ComplexNumber(newReal, newImaginary);
    }

    // 复数相乘
    public ComplexNumber multiply(ComplexNumber other) {
        double newReal = this.real * other.real - this.imaginary * other.imaginary;
        double newImaginary = this.real * other.imaginary + this.imaginary * other.real;
        return new ComplexNumber(newReal, newImaginary);
    }

    // 返回字符串表示形式
    @Override
    public String toString() {
        return "(" + real + " + " + imaginary + "i)";
    }
}

// 示例
public static void main(String[] args) {
    ComplexNumber c1 = new ComplexNumber(3, 4);
    ComplexNumber c2 = new ComplexNumber(-2, 5);

    ComplexNumber sum = c1.add(c2);
    System.out.println("Sum: " + sum); // 输出结果类似 (1 + 9i)

    ComplexNumber diff = c1.subtract(c2);
    System.out.println("Difference: " + diff); // 输出结果类似 (5 - 1i)

    ComplexNumber product = c1.multiply(c2);
    System.out.println("Product: " + product); // 输出结果类似 (-6 + 7i)
}