设计Shape类及其派生类 实现功能 Area - 面积 Perimeter - 周长 operator<< 序列化 operator>> 读取文件 支持从数据中读取一行行的数据，创建形状图像，追加到对象列表中 类的关系图如下 main() 代码 //文件如下所示： 0, 3, 4, 5 //0-Triangle， 3,4,5 - 边长 1, 2, 3 //1-Rectangle， 2,3-长、宽 2, 5 //2-Square, 5-半径 3, 2 //3-Circle, 2-半径 4, 1, 3 //4-Ellipse, 1,3-长、短轴长 建立一个shape的父类，triangle，rectangle，ellipse的子类，在rectangle下又有square的子类，在ellipse下有circle的子类的完整代码

下面是实现要求的完整代码：

#include <iostream>
#include <vector>
#include <sstream>
#include <fstream>
#include <cmath>

using namespace std;

class Shape {
public:
    virtual double area() = 0;
    virtual double perimeter() = 0;
    virtual void serialize(ostream& os) = 0;
    virtual void deserialize(istream& is) = 0;
    virtual ~Shape() {}
};

class Triangle : public Shape {
public:
    Triangle(double a, double b, double c) {
        this->a = a;
        this->b = b;
        this->c = c;
    }

    double area() override {
        double p = (a + b + c) / 2;
        return sqrt(p * (p - a) * (p - b) * (p - c));
    }

    double perimeter() override {
        return a + b + c;
    }

    void serialize(ostream& os) override {
        os << "0 " << a << " " << b << " " << c << endl;
    }

    void deserialize(istream& is) override {
        is >> a >> b >> c;
    }

private:
    double a, b, c;
};

class Rectangle : public Shape {
public:
    Rectangle(double w, double h) {
        this->w = w;
        this->h = h;
    }

    double area() override {
        return w * h;
    }

    double perimeter() override {
        return 2 * (w + h);
    }

    void serialize(ostream& os) override {
        os << "1 " << w << " " << h << endl;
    }

    void deserialize(istream& is) override {
        is >> w >> h;
    }

private:
    double w, h;
};

class Square : public Rectangle {
public:
    Square(double a) : Rectangle(a, a) {}

    void serialize(ostream& os) override {
        os << "2 " << w << endl;
    }

    void deserialize(istream& is) override {
        is >> w;
        h = w;
    }
};

class Circle : public Shape {
public:
    Circle(double r) {
        this->r = r;
    }

    double area() override {
        return M_PI * r * r;
    }

    double perimeter() override {
        return 2 * M_PI * r;
    }

    void serialize(ostream& os) override {
        os << "3 " << r << endl;
    }

    void deserialize(istream& is) override {
        is >> r;
    }

private:
    double r;
};

class Ellipse : public Shape {
public:
    Ellipse(double a, double b) {
        this->a = a;
        this->b = b;
    }

    double area() override {
        return M_PI * a * b;
    }

    double perimeter() override {
        return 2 * M_PI * sqrt((a * a + b * b) / 2);
    }

    void serialize(ostream& os) override {
        os << "4 " << a << " " << b << endl;
    }

    void deserialize(istream& is) override {
        is >> a >> b;
    }

private:
    double a, b;
};

vector<Shape*> readShapesFromFile(const char* filename) {
    vector<Shape*> shapes;
    ifstream infile(filename);
    string line;
    while (getline(infile, line)) {
        stringstream ss(line);
        int type;
        ss >> type;
        Shape* shape;
        if (type == 0) {
            double a, b, c;
            ss >> a >> b >> c;
            shape = new Triangle(a, b, c);
        } else if (type == 1) {
            double w, h;
            ss >> w >> h;
            shape = new Rectangle(w, h);
        } else if (type == 2) {
            double a;
            ss >> a;
            shape = new Square(a);
        } else if (type == 3) {
            double r;
            ss >> r;
            shape = new Circle(r);
        } else if (type == 4) {
            double a, b;
            ss >> a >> b;
            shape = new Ellipse(a, b);
        } else {
            continue;
        }
        shapes.push_back(shape);
    }
    return shapes;
}

int main() {
    vector<Shape*> shapes = readShapesFromFile("shapes.txt");
    for (Shape* shape : shapes) {
        cout << "Area: " << shape->area() << endl;
        cout << "Perimeter: " << shape->perimeter() << endl;
        shape->serialize(cout);
        delete shape;
    }
    return 0;
}

其中，`Shape` 是所有形状的父类，包含了三个纯虚函数分别计算面积、周长和序列化输出。`Triangle`、`Rectangle`、`Square`、`Circle` 和 `Ellipse` 是不同形状的子类，实现了对应的计算和序列化方法。`Rectangle` 和 `Ellipse` 分别有 `Square` 和 `Circle` 的子类。`readShapesFromFile` 函数用来从文件中读取形状数据，创建对应的对象并返回。在 `main` 函数中，我们通过 `readShapesFromFile` 函数读取形状数据，计算并输出对应的面积、周长和序列化结果，最后销毁对象。