设计矩形和立方体面积和体积的类c++

很好，这是一个和数学相关的问题，我可以回答这个问题。以下是设计矩形和立方体面积和体积的类c的示例代码：

class Geometry {
public:
    float area(float length, float width) { return length * width; }
    float volume(float length, float width, float height) { return length * width * height; }
};

class Rectangle {
private:
    float length;
    float width;

public:
    Rectangle(float l, float w) {
        this->length = l;
        this->width = w;
    }

    float getArea() {
        Geometry g;
        return g.area(length, width);
    }
};

class Cube {
private:
    float length;
    float width;
    float height;

public:
    Cube(float l, float w, float h) {
        this->length = l;
        this->width = w;
        this->height = h;
    }

    float getVolume() {
        Geometry g;
        return g.volume(length, width, height);
    }
};

int main() {
    Rectangle r(5, 10);
    Cube c(4, 4, 4);
    std::cout << "The area of the rectangle is: " << r.getArea() << std::endl;
    std::cout << "The volume of the cube is: " << c.getVolume() << std::endl;
    return 0;
}

这个类可以计算矩形的面积和立方体的体积，你可以根据自己的需求进行调整。感谢您的提问！