C++重载操作符

C++重载操作符部分示例

1. 算术操作符：+

#include <iostream>

class Complex {
    
public:
    double real, imag;

    Complex(double r, double i) : real(r), imag(i) {
    }

    Complex operator+(const Complex& other) const {
    
        return Complex(real + other.real, imag + other.imag);
    }
};

int main() {
    
    Complex a(1.0, 2.0), b(3.0, 4.0);
    Complex result = a + b;
    std::cout << "Result: " << result.real << " + " << result.imag << "i\n";
    return 0;
}

2. 比较操作符：==

#include <iostream>

class Point {
    
public:
    int x, y;

    Point(int x, int y) : x(x), y(y) {
    }

    bool operator==(const Point& other) const {
    
        return x == other.x && y == other.y;
    }
};

int main() {
    
    Point p1(1, 2), p2(1, 2), p3(3, 4);
    std::cout << "p1 == p2: " << (p1 == p2) << "\n";
    std::cout << "p1 == p3: " << (p1 == p3) << "\n";
    return 0;
}

3. 赋值操作符：+=

#include <iostream>

class Counter {
    
public:
    int value;

    Counter() : value(0) {
    }

    Counter& operator+=(int increment) {
    
        value += increment;
        return *this;
    }
};

int main() {
    
    Counter counter;
    counter += 5;
    std::cout << "Counter: " << counter.value << "\n";
    return 0;
}

4. 流操作符：<<

#include <iostream>

class Vector2D {
    
public:
    double x, y;

    Vector2D(double x, double y) : x(x), y(y) {
    }

    friend std::ostream& operator<<(std::ostream& os, const Vector2D& vec) {
    
        os << "(" << vec.x << ", " << vec.y << ")";
        return os;
    }
};

int main() {
    
    Vector2D vec(1.0, 2.0);
    std::cout << "Vector: " << vec << "\n";
    return 0;
}

5. 下标操作符：[]

#include <iostream>

class Array {
    
    int* data;
    size_t size;

public:
    Array(size_t size) : size(size), data(new int[size]) {
    }

    ~Array() {
    
        delete[] data;
    }

    int& operator[](size_t index) {
    
        return data[index];
    }
};

int main() {
    
    Array arr(3);
    arr[0] = 10;
    arr[1] = 20;
    arr[2] = 30;

    for (size_t i = 0; i < 3; ++i) {
    
        std::cout << "arr[" << i << "] = " << arr[i] << "\n";
    }
    return 0;
}

6. 函数调用操作符：()

#include <iostream>

class Adder {
    
    int value;

public:
    Adder(int value) : value(value) {
    }

    int operator()(int x) const {
    
        return x + value;
    }
};

int main() {
    
    Adder addFive(5);
    std::cout << "Add 5 to 3: " << addFive(3) << "\n";
    return 0;
}