动态联编示例

#include<iostream>
using namespace std;

class Shape {
public:
    virtual double area() const = 0;
};

class Rectangle : public Shape {
private:
    double width;
    double height;
public:
    Rectangle(double w, double h) : width(w), height(h) {}
    virtual double area() const {
        return width * height;
    }
};

class Circle : public Shape {
private:
    double radius;
public:
    Circle(double r) : radius(r) {}
    virtual double area() const {
        return radius * radius * 3.14159;
    }
};

int main() {
    Shape* shape;
    Rectangle rec(3, 4);
    Circle cir(2.5);

    shape = &rec;
    cout << "Rectangle 测试: area = " << shape->area() << endl;

    shape = &cir;
    cout << "Circle 测试: area = " << shape->area() << endl;

    return 0;
}
//gpt