c++怎么实现运算符重载_c++运算符重载实现与示例

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class Vector2D {
public:
    double x, y;
<pre class='brush:php;toolbar:false;'>Vector2D(double x = 0, double y = 0) : x(x), y(y) {}

// 重载 + 运算符
Vector2D operator+(const Vector2D& other) const {
    return Vector2D(x + other.x, y + other.y);
}

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Vector2D a(1.0, 2.0);
Vector2D b(3.0, 4.0);
Vector2D c = a + b; // 调用 operator+
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Vector2D operator+(const Vector2D& v1, const Vector2D& v2) {
    return Vector2D(v1.x + v2.x, v1.y + v2.y);
}
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class MyString {
private:
    char* data;
<p>public:
MyString(const char* str = nullptr) {
if (str) {
data = new char[strlen(str) + 1];
strcpy(data, str);
} else {
data = new char[1]{'\0'};
}
}</p><pre class='brush:php;toolbar:false;'>// 赋值运算符重载
MyString& operator=(const MyString& other) {
    if (this == &other) return *this; // 自赋值检查

    delete[] data; // 释放原有资源
    data = new char[strlen(other.data) + 1];
    strcpy(data, other.data);

    return *this;
}

~MyString() {
    delete[] data;
}

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bool operator==(const Vector2D& other) const {
    return x == other.x && y == other.y;
}
<p>bool operator<(const Vector2D& other) const {
return x < other.x || (x == other.x && y < other.y);
}
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// 输出运算符重载
std::ostream& operator<<(std::ostream& os, const Vector2D& v) {
    os << "(" << v.x << ", " << v.y << ")";
    return os;
}
<p>// 输入运算符重载
std::istream& operator>>(std::istream& is, Vector2D& v) {
is >> v.x >> v.y;
return is;
}
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Vector2D v;
std::cin >> v;
std::cout << v << std::endl;
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