作为函数参数的C++类对象

#include <iostream>

class MyClass {
public:
    int value;
    MyClass(int v) : value(v) {}
};

// 值传递
void passByValue(MyClass obj) {
    obj.value = 10;
}

// 引用传递
void passByReference(MyClass& obj) {
    obj.value = 20;
}

// 常量引用传递
void passByConstReference(const MyClass& obj) {
    std::cout << "Value: " << obj.value << std::endl;
}

int main() {
    MyClass obj(5);

    passByValue(obj);
    std::cout << "After pass by value: " << obj.value << std::endl; // 输出 5

    passByReference(obj);
    std::cout << "After pass by reference: " << obj.value << std::endl; // 输出 20

    passByConstReference(obj);
    std::cout << "After pass by const reference: " << obj.value << std::endl; // 输出 20

    return 0;
}