using System;

// 自定义复数类
public class Complex
{
    // 复数的实部和虚部
    public double Real { get; set; }
    public double Imaginary { get; set; }

    // 构造函数
    public Complex(double real, double imaginary)
    {
        Real = real;
        Imaginary = imaginary;
    }

    // 重载 + 运算符
    public static Complex operator +(Complex a, Complex b)
    {
        return new Complex(a.Real + b.Real, a.Imaginary + b.Imaginary);
    }

    // 重载 - 运算符
    public static Complex operator -(Complex a, Complex b)
    {
        return new Complex(a.Real - b.Real, a.Imaginary - b.Imaginary);
    }

    // 重载 * 运算符
    public static Complex operator *(Complex a, Complex b)
    {
        double real = a.Real * b.Real - a.Imaginary * b.Imaginary;
        double imaginary = a.Real * b.Imaginary + a.Imaginary * b.Real;
        return new Complex(real, imaginary);
    }

    // 重载 ToString 方法
    public override string ToString()
    {
        return $"{Real} + {Imaginary}i";
    }
}

class Program
{
    static void Main()
    {
        // 创建两个复数对象
        Complex complex1 = new Complex(1, 2);
        Complex complex2 = new Complex(3, 4);

        // 使用重载的 + 运算符
        Complex resultAddition = complex1 + complex2;
        Console.WriteLine("Addition: " + resultAddition);

        // 使用重载的 - 运算符
        Complex resultSubtraction = complex1 - complex2;
        Console.WriteLine("Subtraction: " + resultSubtraction);

        // 使用重载的 * 运算符
        Complex resultMultiplication = complex1 * complex2;
        Console.WriteLine("Multiplication: " + resultMultiplication);
    }
}