原型模式

 

#include<cmath>
#include<iostream>
using namespace std;

class Vector {
private:
    double *array = new double[4];
    double length;
public:
    Vector(double arr[4])
    {
        this->array[0] = arr[0];
        this->array[1] = arr[1];
        this->array[2] = arr[2];
        this->array[3] = arr[3];
        this->length = sqrt(((arr[0] - arr[1])*(arr[0] - arr[1])) + ((arr[2] - arr[3])*(arr[2] - arr[3])));
    }
    ~Vector()
    {
        delete[]array;
        this->length = 0;
    }
    Vector* clone()
    {
        return new Vector(*this);
    }

    Vector(const Vector& vector)
    {
        //浅克隆
        this->array = vector.array;
        this->length = vector.length;

    }
    void show()
    {
        cout << "向量长度：" << this->length << endl;
    }
};
int main()
{
    double s[4] = { 1, 2, 3, 4 };
    Vector* v1 = new Vector(s);
    Vector* v2 = v1->clone();
    v1->show();
    v2->show();
    return 0;
}