帮我用C++写一个结构体，包含+-*/重载运算符，拷贝函数，赋值函数，友元函数

好的，以下是一个示例：

#include <iostream>
using namespace std;

struct MyStruct {
    int a, b;

    MyStruct(int a = 0, int b = 0) : a(a), b(b) {}

    // 加法运算符重载
    MyStruct operator+(const MyStruct& other) const {
        return MyStruct(a + other.a, b + other.b);
    }

    // 减法运算符重载
    MyStruct operator-(const MyStruct& other) const {
        return MyStruct(a - other.a, b - other.b);
    }

    // 乘法运算符重载
    MyStruct operator*(const MyStruct& other) const {
        return MyStruct(a * other.a, b * other.b);
    }

    // 除法运算符重载
    MyStruct operator/(const MyStruct& other) const {
        return MyStruct(a / other.a, b / other.b);
    }

    // 赋值函数
    MyStruct& operator=(const MyStruct& other) {
        a = other.a;
        b = other.b;
        return *this;
    }

    // 拷贝函数
    MyStruct(const MyStruct& other) {
        a = other.a;
        b = other.b;
    }

    // 友元函数
    friend ostream& operator<<(ostream& os, const MyStruct& obj) {
        os << "a: " << obj.a << ", b: " << obj.b;
        return os;
    }
};

int main() {
    MyStruct a(1, 2), b(3, 4), c;

    // 测试加法运算符重载
    c = a + b;
    cout << "a + b = " << c << endl;

    // 测试减法运算符重载
    c = a - b;
    cout << "a - b = " << c << endl;

    // 测试乘法运算符重载
    c = a * b;
    cout << "a * b = " << c << endl;

    // 测试除法运算符重载
    c = a / b;
    cout << "a / b = " << c << endl;

    // 测试赋值函数
    MyStruct d = a;
    cout << "d = " << d << endl;

    // 测试拷贝函数
    MyStruct e(a);
    cout << "e = " << e << endl;

    return 0;
}

输出结果：

a + b = a: 4, b: 6
a - b = a: -2, b: -2
a * b = a: 3, b: 8
a / b = a: 0, b: 0
d = a: 1, b: 2
e = a: 1, b: 2